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BIOL 3324 Human Physiology - BIOL3324_lecture04_0831
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00:03 All right, y'all you ready for weekend? Yeah. Does your weekend
00:07 right after this class? Some people like, yeah. So for those
00:12 you whose weekend starts early? good. Let me ask anyone going
00:16 the football game, one person raised hand. All right. I don't
00:21 football. It's usually the response. , you know, it's a social
00:27 . Grab a bunch of friends, and yell. It's much more fun
00:30 high school football. So go, in the big 12 now. What
00:36 that mean? What it means is we're going to be getting about $40
00:40 a year just for existing. So , it's a big deal,
00:45 When is the game? I don't , it is Saturday, but I
00:49 know what time Saturday we're playing UTS . This is actually, I know
00:53 sounds like I'm a big football I live breathe. I hate pro
00:58 . College football is where I High school football is a lot of
01:01 , but this is the first time a very long time. U
01:05 I think we have seven Texas teams our schedule this year, which is
01:10 . It just makes people like me . Um, oh, just because
01:15 forgot totally on Tuesday. Uh, test sign up at classes open if
01:21 didn't know. Um, so some you are like, what?
01:25 Um, just remember we don't have on the day, we have exams
01:28 so that means the exam is 10 or, I, it's not 10
01:33 but whatever, it's two weeks from . So, what is that?
01:37 days away? All right. I that's kind of scary sounding. It's
01:42 that big of a deal. All . Uh, so today, what
01:46 gonna do is we're going to finish with cell signaling and we're gonna move
01:49 electrical signaling. What was the electrical reading? Like you can say it
01:56 on, it's a thick and dense boring, wasn't it? Some of
02:02 going, I didn't read it. . Ok. Fine. All
02:06 So what we're gonna do is we're finish up with, uh, a
02:09 . We're going to kind of move how hormones work and what the hormones
02:13 . And then we're going to look the electrical signaling. Our starting point
02:16 here. And I want to remind , remind you guys, I guess
02:21 is the pattern of signaling through a in a cell? What do
02:24 what do we expect? The first to see? We have a
02:27 What's going, what's going to be with the receptor? Log in log
02:31 by the receptor. What does it ? Receptor? When it becomes
02:36 it activates a transducer transducer then activates , an enzyme of some sort.
02:44 then usually there might, well, usually, but sometimes there is a
02:48 messenger and second messenger activates in. . You guys learned it or at
02:54 some people did. All right, got that. You've already understand everything
02:57 gonna talk about today. Here's the example, these, these are the
03:00 receptors. All right, they're a different looking, but the same things
03:05 . All right. So you can over here, uh these are the
03:08 types. Um Some of these you have heard of, you've heard of
03:12 F beta TGF beta tumor. never heard of that one.
03:18 Uh How about I thought this would it. Usually insulin receptor is another
03:24 , growth hormone receptor. You've heard growth hormone, right? So look
03:28 these, you see here, what have with these types of receptors is
03:33 have a receptor region on the, the internal side or on the interstitial
03:39 side. And then inside the we have a region that has some
03:43 of enzymatic activity. All right. we don't have a transducer immediately
03:48 Instead, we're going to have an that's probably by or bypassing that first
03:54 , but it's basically the same right. So here you can see
03:57 a K A, here's kinase uh the uh TKARS, you don't have
04:04 region, it's actually just directly associated the kinase. Typically. What these
04:09 , you can see that they're Dir So dimer dimer dimer dimer,
04:13 you don't know what a dimer is one M mono dimer, right?
04:18 it's just two of them and then you activate them, they're just going
04:22 go through the same sort of All right. And this is kind
04:25 what it looks like. If you at the next slide, sorry.
04:27 we go. Here's an example. one is this one? Does it
04:31 ? Nope. All right. But can see right here we got the
04:35 , they bind the receptor, the forms a dir, it won't work
04:38 a single, it always has to a dimer in this particular case.
04:41 here you can see its kine it activates an enzyme which activates another
04:48 which activates maybe what we call a messenger. We'll just go ahead and
04:52 it a second messenger first which activates effect or which activates an infector,
04:56 does stuff. Do you see? it doesn't matter what type of system
05:01 looking at it all basically does the same thing, right? So what
05:06 when this, when we activate a like this, if we activate any
05:10 of system that's working through a a uh basically through one of these uh
05:17 cascades, we can have one of two things, right? So what
05:21 been seeing kind of these pictures over is we're activating a cascade that is
05:27 the nature of the proteins that are in existence, right? So we're
05:32 something that lacks phosphorylation and we're phosphorylation . That's what the big P stands
05:37 . And phosphorylation, typically, the typical is usually your activating molecule,
05:43 sometimes it could be your deactivating which screws everything up and makes things
05:47 harder. But we can think in of activation is that OK today?
05:50 . But also one of the things can happen is is I'm not just
05:54 proteins that are already there. I actually activate gene expression and this is
05:59 these are two trying to show So here we can see a
06:02 right? G protein coupled receptor activating Adal cycles, activating through protein kine
06:09 protein K A activates molecules that are transcription factors that have become activated and
06:18 turns on gene transcription. All Here's an example through Interferon. Have
06:24 ever heard of Interferon? Yes. . OK. You ever feel achy
06:29 you get the flu? Right? Interferon. That does that, that
06:35 that your body gets. That's every in your body screaming at you that
06:39 been infected by a virus interfere on is the, when this happens,
06:43 interfere on alpha, you don't even that. That's a trivial pursuit
06:46 That's just something you keep in your pocket saying I'm all achy and then
06:49 go. Yeah, that was when Wayne taught me about interfering gamma.
06:53 ? But here you go. Oh , there's a Interferon gam right
06:55 These typically work through the jack stat again, not something you need to
06:59 . Just it's a, it's a cascade that is used in different
07:04 And what does it do? You the proteins through those enzymes, those
07:08 then translocated. And what do they as transcription factors turn on genes or
07:13 off genes and it's the same thing here. All right. So the
07:17 here is I'm activating things that are present when I have these types of
07:24 . When I'm working through a membrane , I am turning something on or
07:29 turning something off, it already If I walk in this room and
07:32 room is light and I want to it dark. I press a
07:35 everything turns off. If I want make the room light again, I
07:38 a button, everything is already in room to make the room light,
07:43 . So this is a very quick pathway and this is how many of
07:47 signaling pathways already work. All the is already in place. We just
07:51 to turn it on or off, . It's through a cascade of events
07:55 because you can have multiple targets you're not just acting like 1 to
07:59 to 3 to 4 to 5, going one and one prime and one
08:04 prime and then 22 prime prime, prime prime prime prime. And you
08:07 just kind of see just cascades out gets larger and larger and larger.
08:11 you can get massive effects from small . The second type of signaling that
08:17 see in the body is through nuclear , which is a horrible name for
08:21 receptor. And the reason it's a name is because you find nuclear receptors
08:26 the cytosol as well as in the when it's not bound and when it's
08:31 active, it's just kind of hanging inside the cell waiting to be
08:35 It's like I'm just waiting around. . In the first case, what
08:38 were looking at when we were looking uh plasma membrane bound receptors, where
08:43 the binding protein? Where was the found on the outside of the
08:48 Right. So with a nuclear what we're going to be dealing with
08:52 we're going to be dealing with a that moves into the cell. All
08:56 . It's typically lipophilic, not typically a molecule that can penetrate through
09:02 plasma membrane without any aid whatsoever. what it will do is it will
09:07 up to a nuclear receptor usually in side as well, but it could
09:09 so in the nucleus as well because it kind of goes wherever it wants
09:13 . But once it binds up, , what happens is, is you'll
09:16 one bound receptor, you'll find another receptor, they'll come together, they'll
09:21 to the nucleus. And now your receptor ligand complex becomes a transcription
09:27 There are no middle men, there no effectors along the way, the
09:32 itself plus the ligand becomes the molecule doing the work. And here you're
09:37 to turn things on or you're going turn things off again. And
09:40 we typically think of turning things So that's kind of what you're seeing
09:44 this particular uh uh system here, ? So you can see, oh
09:48 , I have a thyroid hormone. have glucocorticoid hormone. Have you ever
09:51 of those hormones? All right, is a steroid, this is
09:55 I mean hormone, they're both lipophilic they can pass through the membrane,
10:00 problems whatsoever. They're just like, , in fact, they prefer uh
10:04 environments, not water environments. And will happen is see, we bind
10:09 and it says, OK, I'm to move in and I'm going to
10:11 a dimer and now I'm acting as transcription factor over here. I'm creating
10:15 strange type of dimer. This would referred to as a homo dier.
10:20 would be a hetero dier. All . So again, I'm not gonna
10:25 you which is which it's just. when you hear those terms, it's
10:28 OK. I know prefixes, I how to apply them. All
10:32 But in both cases here, what I doing is I'm making, uh
10:37 making new molecules. I'm going through process of DeNovo protein synthesis, you
10:43 , DeNovo means of new just in . Right. So if I'm trying
10:47 turn off the lights in the room I have this process, I don't
10:51 lights, I don't have wiring and don't have a switch. What am
10:55 doing? I'm building the switch, building the lights and I'm building the
11:00 so that I can turn it on turn it off. Right. So
11:04 a slower process, but it's a lasting process, generally speaking. All
11:10 . And so these are two different of strategies cells use for this type
11:14 work. Now, I have something this up here where it's a
11:18 simple way to help you understand and the kind of things that we just
11:21 of looked at. All. So we did a lot of second
11:24 systems yesterday and we looked at our bound receptors either way you want to
11:28 at it. And so you just , ok, I've got some
11:30 What do I need know about these ? Well, what kind of characteristics
11:34 ligands do the lions have in either these two cases? Well, the
11:40 one is nuclear because it's lipophilic. that means it's going through the membrane
11:44 the other one is stuck on the side. So this must be,
11:46 is, starts with an H and still loves it. Hydrophilic. Thank
11:53 . All right. That's, that's . So, then you go.
11:56 . Well, what about its Well, if it's lipophilic, it's
12:01 . It passes through. If it's , it's not permeable. Ok.
12:04 about its location? Where is the located? Well, one's in the
12:07 and one is in the cytosol slash . All right, membrane bound
12:14 Do they have second messengers? Sometimes nuclear bound or nuclear receptors? Do
12:19 have second messengers? No. Do see how we do this? It's
12:23 straightforward mechanisms of action. You use signaling cascade to activate whatever is
12:29 In the other case, you're acting a transcription factor. What's your effector
12:34 downstream? The effector the actual nuclear itself? What is the rate of
12:41 ? So if you have everything already place, what's your rate of response
12:45 ? And what if you don't have in place? Slow? Now,
12:48 are relative terms. All right, you an example of fast versus
12:52 Right? When I was a grad , the work that I used to
12:55 was on a membrane bound receptor. was working through a PK A pathway
13:02 a pathway, I would inject my with uh whatever uh stimulant I was
13:09 it within 30 seconds. I would seeing a response. I'd have to
13:15 do all the plates that, that and I'd take the first plate
13:17 I'd freeze it so I could halt response. And then I'd do a
13:21 time, point a two minute point a five minute time, 0.10
13:25 hour. And I'd work it all way up to, uh, two
13:29 and you could see the response like I was an under, uh,
13:33 I was a grad student. So was when I was a post back
13:36 post back post doc when I was grad student, I worked with androgen
13:39 , which is a steroid, worked a nuclear receptor and in the androgen
13:44 even bother looking for about a So just give you a sense of
13:48 quick. All right. So what want to do is I want to
13:53 this little bit of knowledge that we these membrane bound receptors versus nuclear
13:57 And I want to address the question how do we go about signaling?
14:00 right. Now, I put this the front of the lecture of,
14:04 , of, of physiology. Sometimes don't see this stuff until way towards
14:08 end. All right. But I this type of signaling is really important
14:12 it doesn't matter what system you're looking , you're going to be pointing at
14:16 endocrine system. That's what this kind thing is saying is like this is
14:19 endocrine system. The thing is is the endocrine system is literally a bunch
14:24 organs that send out chemical signals to systems. And so they kind of
14:28 thrown into a box just because of signaling. And very early on when
14:33 were studying and learning about hormones, made sense that we, we kind
14:37 separated them out until we learned that signals. Your stomach is an endocrine
14:43 , right? Have you ever thought that? It tells your, for
14:49 , the stomach tells your small intestines to do and when to do it
14:53 it doesn't do it through nerves, start digesting food, not because you
14:58 uh a signal from your brain saying to digest. It's because food shows
15:04 , right? And so it's an organ and this is what this is
15:08 to show you that here are what the classical endocrine organs, right?
15:13 so these uh underneath them are kind listed as the classical hormones. All
15:19 . So with that in mind, want you to understand that most of
15:23 things we're looking at are endocrine, though we may not classify it as
15:28 . And what this list is is to show you like. All
15:30 Well, what's a hormone if these the classical hormones? What are
15:34 Well, they're basically a chemical secreted a cell, single cell or a
15:38 of cells. How very helpful and they're gonna do is that, that
15:42 goes out into the blood and then around the body and finds a cell
15:46 the receptor there. We already saw definition. Tuesday. Gotta remember what
15:51 it is, right? Gotta keep . It's the weekend, it's the
15:55 . Right now. We don't put lot of hormone out there. It's
15:59 hormones act because of the systems that work through in very, very,
16:04 low molar concentrations, I think at bottom. I, yeah, nano
16:09 PICO molar concentrations. So just in you don't know what those two numbers
16:14 . 10 to the minus 9, in the minus 12. So
16:19 very small amounts, but they have massive effects because of those large cascades
16:26 they create. We have some very definitions. It wasn't just that they
16:32 traveling some distance. It was all right. So a hormone has
16:36 , this and this and then what started doing is we started discovering other
16:39 molecules. So, um have anyone taken immunology yet? I don't know
16:44 it's offered, it's not offered every . Sometimes they used to offer it
16:48 year. But that's not really a anymore. There's a hormone of the
16:53 system. It's a group of hormones the immune system. You heard about
16:56 enough during COVID, they're called Have you ever heard of those?
17:03 , cytokines? All right, cytokine all the characteristics of a hormone except
17:09 it's not secreted from an organ, secreted from a circulating cell for the
17:13 part. So, the line on we call a hormone has common kind
17:19 blurred. All right. So we kind of say, all right.
17:23 , we're just gonna call it cell for now. All right.
17:27 for our purposes though, let's look some of the characteristics. What is
17:32 the origin of secretion? Well, , generally speaking, can be secreted
17:37 glands. Glands are tissues that are from some sort of epithelium. And
17:43 , you're sitting there going, I've taken developmental biology. I barely know
17:46 epithelium is. Epi on top of , right? It's all right.
17:53 think we should require one to take development class at least if you're a
17:59 . All right. But then this why I say here's the problem,
18:02 ? We got individual cells, neurons secrete hormones, we call them
18:07 hormones to distinguish them the immune system hormones, they're called cytokines to distinguish
18:15 . Most of the hormones are gonna secreted into the bloodstream. So,
18:19 right, that's the good definition. there are such things as ecto
18:24 All right. Now, humans not much. Although ladies, I'm just
18:29 let you know now when you have kid, you'll be able to recognize
18:31 child by smell. All right. of that is one because everyone has
18:38 unique odor that they produce. Number as your sense of smell is a
18:42 times greater than any man. That's scientifically proven like 10 to the six
18:48 more powerful. Which makes sense once start hanging out with guys and you're
18:52 , man, you stink. I know what you're talking about. I
18:54 smell anything. All right, that . All right. But anyway,
18:59 hormones. Um, do you guys learning about the moths that find each
19:02 , each other in the dark? know, and they do it solely
19:05 a sense of smell. No, didn't learn that one. They usually
19:09 about bio one. Those are ecto . That's how you discover it.
19:14 term for an ecto hormone. You have heard of these pheromones.
19:18 they're an ecto hormone. All Targets, right? Targeting tissues.
19:22 can be local, right? Or can be some distance away, which
19:28 confounding because we're talking about long distance . But if you're locally oriented,
19:32 is that not paracrine signaling? Because the answers because that's just what we
19:39 . We're gonna tell you a definition then we're just gonna kick it around
19:42 beat it up for a little bit hospital. So typically what we say
19:48 that we call it a hormone because actually goes into the bloodstream. That's
19:52 of the key thing there. Now , yes, right. Now,
19:58 classic example, we're gonna see one now of local is signaling between the
20:04 and the pituitary gland. You from our perspective, that's pretty darn
20:08 because those two structures are a couple millimeters apart, but they are two
20:12 , unique structures and they are a away from each other. So what
20:16 local mean? You have to start terms so that we are all on
20:21 same page? And I don't think that significant. Right. But
20:24 so the point being that a hormone in the blood and goes some
20:29 All right, the last one, have to make sure that when you're
20:33 about target cells, you understand that target cell must have the receptor to
20:36 hormone that is actually acting on So you can wash your body in
20:40 hormone. But if you don't have right receptor for it, it's not
20:43 do anything. So the receptor which is why we spend so much
20:48 talking about receptors. All right. up here we can see just I
20:54 these pictures up here because you you will say hormones over and over
20:57 and I kind of want you to what you're dealing with. I
20:59 have you ever wondered why you take chemistry? I mean, it's a
21:04 , right? If you're a biology , you have to take organic
21:07 If you're planning on metal color you gotta take that dreaded two,
21:13 ? Why? So when you point that picture you're like, oh
21:15 I've seen a molecule. That kind looks like that before. Right.
21:20 say it out loud. But organic , one is a vocabulary class.
21:26 tell Doctor Bean. I said All right. The thing is,
21:32 there's a lot of different ways to molecules and specifically hormones. There's a
21:37 different ways you can look at it say, how is this thing
21:40 All right. So source of you know, is it a hypothalamic
21:44 is a pituitary hormone? Is it hormone? Yada yada yada,
21:48 But that makes all these lists and kind of hard, right? And
21:51 not about making hard lists. All . I think the best way to
21:55 something is to simplify things as much possible. All right, another way
21:59 to look at it mechanism of In other words, what type of
22:02 that does it use? And so already seen that there are two basic
22:05 of receptors, membrane, brown versus . And that's kind of a nice
22:08 to do things except it makes things in some cases. So it might
22:14 an easy, there might be an way to do it. I think
22:17 easiest way to look at something is look at its solubility in water because
22:21 already going to define for you what of receptor it's gonna use,
22:25 Is it water soluble or is it water soluble if it's not water
22:29 That means it is lipid soluble? right. So that's an easy way
22:33 do it. But another way to it, which I think complicates matters
22:37 little bit and I'll show you why complicates is the latter one which is
22:40 the chemical class. Is it a protein or is it a steroid or
22:45 it a me? And so now we have three classes. Whereas
22:49 you're looking at water solubility, you're at two classes, right? And
22:55 what do you think is easier? classes or two? I'd rather do
23:00 . All right. And then just of learn which one falls into what
23:04 ? OK. So let's see if make sense. And if you think
23:07 have a better way, that's You use your way. All
23:10 But I want to first start here the actual types of classes that
23:15 the uh what I call the chemical , right? So you'll see why
23:19 do it this way first. But we're really doing here is we're focusing
23:24 the water solubility. See, peptides proteins are water soluble, right?
23:33 love water environments. How do we them? How do we make a
23:41 ? Exactly. That's what it sounds when a lot of people answer,
23:46 great. I love it. II prefer the, you could probably even
23:50 that noise from where you're sitting and be like, yeah, a good
23:53 . All right. Process of Translation, right. DNA to RN
23:58 protein, protein is made in the reticulum processed through the Golgi modified in
24:05 goal G stored up in vesicles and in the vesicles until needed. All
24:11 . So that's the general process in you make them when it's time to
24:15 them. You take that, you it to the plasma membrane, you
24:19 it out into the environment off, goes into the interstitial fluid, out
24:22 the bloodstream, travel around the find the receptor. It does its
24:25 . OK. Now, the key you'll notice here is that I'm always
24:29 it, there's a constitutive mechanism. releasing it in a regulatory fashion,
24:35 ? So it's being released when I it to, that means I'm storing
24:38 up in a vesicle filled with what ? That's a good answer,
24:44 So I'm making it in a and it in a water environment and when
24:48 release it out, I'm releasing it into a water environment. It's not
24:53 that plasm membrane. I can store . Right. That's the idea
24:57 I can hold on to this until time to release. All right,
25:01 it goes out into the external into the interstitial fluid, out into
25:05 bloodstream, it's comfortable and happy and can float around there. Right?
25:10 are things that can bind to it increase its half life in circulation.
25:15 for the most part, it is of surviving independent of any sort of
25:20 binding protein. All right. And how does it act well because it
25:24 pass through a membrane, it's going act through what type of receptor,
25:29 bound receptors, right? G protein receptors, tyrosine kins yada,
25:35 yada yada yada catalytic receptors, you , you name it, right?
25:38 will be membrane bound ligands receptor activates signaling cascade. Something happens down the
25:44 through an effector so far. Have learned anything really new there?
25:49 OK. So we kind of have vision of what a peptide or a
25:53 does steroids. I love up. , that's not. That's just the
25:59 of action. I got ahead of . See. All right. So
26:02 just shows you look how do we . It. Look, it doesn't
26:05 if I hear you can see the of the proteins here, you know
26:08 peptides or sorry, the the So here we got a G protein
26:12 receptors look 123 different different hormones. Down here, look what we
26:17 We have a catalytic receptor, catalytic , catalytic receptor, different types of
26:23 , but they're all acting through these bound proteins. All right,
26:31 I love this. I love this . Is that an awesome picture you're
26:35 at it and you're seeing a bunch colors and a bunch of lines and
26:38 like, I don't know if you've seen this picture. It is a
26:41 me tell you what's going on up . This is cholesterol. All steroids
26:45 derived from cholesterol. You've been told entire lives that cholesterol is bad for
26:49 , right? We already said cholesterol important for maintaining the plasma membrane.
26:54 else do you need cholesterol for making your steroids? Ok. Absolutely.
27:00 vitamin D you need cholesterol. Don't cholesterol. All right, you just
27:06 want an overabundance of it. So what this chart is showing you not
27:11 you to memorize, but so that can look at it and be smarter
27:14 everybody else that you know. Right that it says look, I go
27:17 cholesterol and I migrate along a path a specific hormone dependent upon the presence
27:24 specific enzymes. Right. So this group, these are the progestins.
27:31 lavender is that lavender. Ok. is the androgens, what you might
27:36 the testosterones. OK. Down I don't know what that color
27:40 The less lavender perry winkle. Come , help me out ladies, I
27:45 I know seven colors pink. We're gonna go with pink. This
27:51 are the estrogens. OK? Up , that's the mineral corticoid. Down
27:56 . Those are the glucocorticoids and each these lines represent the primary enzyme responsible
28:03 lead you down that path. So for example, if you want
28:08 make estrogen, you start off with , you pass through the progess,
28:12 through the androgens and then you go here and there's estradiol that is uh
28:17 estrogen when we talk about estrogen, the one that we think of.
28:21 right now, the key thing in one of these steroids is that you
28:25 to have the right enzymes in place order for it to happen. And
28:28 gonna give you an example of why important to know a little bit of
28:32 before you start opening your mouth in media. OK. So a couple
28:36 years ago, there was a very woman in uh the UK who was
28:40 upset that men didn't get to experience , right? It's not fair that
28:45 don't get to experience the hardships of . So I think she said that
28:51 should dose men with progesterone so that can experience what women experience when they're
28:57 . And I read that and I and laughed and laughed and said that
28:59 woman. Now, why did I she's a stupid woman? What happens
29:04 you give a man progesterone? Take look at that chart. You tell
29:11 what do you think happens? Nothing. No men have progesterone in
29:22 , say what? They convert it away to testosterone. So if you
29:28 a man a whole bunch of he's going to convert it right into
29:32 . And that manly man who you're to make into a miserable pregnant woman
29:37 going to be a more manly man . So, do you see the
29:43 of kind of understanding these things? , why don't women stop being
29:47 Why don't, why don't they stop become manly men? If I gave
29:51 woman progesterone and presuming that it wasn't stop at progesterone, what's gonna
29:57 It's gonna go down and then it's to go across because she has aromatase
30:01 convert the testosterone, the android into . All right. So the reason
30:09 don't stop at androgens is because you the right enzymes to make that
30:14 All right. Now, again, don't have to memorize this chart.
30:17 know this chart because I worked with stuff for years and years and years
30:20 years. And if you ask me the different enzymes, I'd be
30:23 I don't know, it's been years years and years since I've looked at
30:25 . Right. But the idea here that these steroids are unique from each
30:31 because of the right enzymes. And we've done is we've done small side
30:35 changes to these, uh this, cholesterol molecule to make the molecules unique
30:42 each other. It's kind of cool you think about it. Now,
30:47 I make it, they're made in tissues, you have to have the
30:51 enzymes available. And because you're dealing lipids, you can't store up a
30:57 inside a vesicle. So as soon I make testosterone, what's it gonna
31:03 off, it goes the moment you estrogen, what's it gonna do
31:08 It goes Glucocorticoid. So, the that we regulate the production of a
31:13 , is it at, we're always it or do we have to tell
31:17 cell when to make it? What you think to have to tell the
31:22 because I can't store it up and you can hold on to that until
31:25 time. Right? That's the All right. So I synthesize on
31:33 and I release as I make That's the idea here. And what
31:38 have is this a very pulsatile production hormones just as an idea. All
31:43 . So now we've released hormone, is a lipid that wants to hang
31:47 with lipid and you're releasing it into interstitial fluid. Do you think that
31:52 is happy? What do you think I put a fat in water?
31:56 it happy? What does it want do wants to find other fat or
32:01 wants to hide? Right. That's you're doing that, right. It
32:05 something to bind it up and sequester and protect it. All right.
32:10 is where binding proteins come in, ? So, circulating in your blood
32:14 any given time are a series of proteins, proteins specific and non specific
32:19 that are capable of binding up lipid molecules to ensure that one that they
32:26 in the blood where they're supposed to because if they had their druthers.
32:30 they followed their chemical nature, they find the first amount of fat they
32:33 and just hang out there and say not ever getting out of this.
32:38 ? So that allows them to stay circulation and then what they do is
32:43 have to follow these rules of mass , right? Do you remember
32:48 those, those rule? I we talked about the cookies and
32:51 you know, eating the cookies and them on the plate. So really
32:55 I'm saying is free versus bound You've learned about those previously.
33:00 please tell me. Yes, one nodding their head, right? So
33:05 , in, in your body, have molecules that are bound up in
33:08 way, we call those biologically inactive they're not available for use, but
33:12 have free molecules are available, So those are active, biologically active
33:19 there's a perfect ratio for what those , what that ratio is depending upon
33:23 molecule you're looking at. So for , I think fructose, what is
33:27 ? The 16 fructose? It's like to 1 and you're like, but
33:30 not equal, but that's what the likes, right? So you're in
33:34 balance and so as you take things and they interact with their receptors or
33:41 from the blood, you've put that out of balance. And so that
33:44 more to become unbound. If you more into the system, more is
33:47 to become bound itself. And so always balancing around free versus unfree or
33:52 versus bound. All right. So transported in the blood by carrier
34:00 Some of them are specific, some non-specific, they're released based on the
34:05 properties of that proper ratio for uh around the law of mass action or
34:11 of mass balance. When they're they go hunting first thing for some
34:17 . So they go into the platinum . And what we don't talk about
34:20 lot is that once they go inside cell, there's usually a binding protein
34:23 that grabs them, holds onto them says, I'm going to stick you
34:26 you need to go and then goes delivers it to say a nuclear
34:30 All right. Not always but very . That's what happens. And so
34:34 you're bound up to your nuclear Once that new, the receptor gets
34:37 up, it doesn't want to be out on the side is all it
34:41 for a partner that also has been up. That's when they come
34:44 create that dimer, they translocated or translocated, they show up in the
34:49 , they bind to a response element front of a gene. So they
34:55 as a transcription factor and then they gene expression. OK. So this
35:03 showing you that mechanism of action. right. Again, it's not different
35:08 what we just previously saw. But can see there's a steroid, it
35:12 in, finds its receptor trans locates eyes starts transcription, you get DeNovo
35:18 synthesis. So if you're looking at two classes, you know, in
35:24 of peptide versus steroid, that's an way to kind of say. All
35:28 , that's great. But then we up with this weird one, these
35:31 , which is why I say we try to memorize along the amines because
35:34 of means behave like peptide. Some means behave like steroids and how do
35:40 behave? Well, it's based around lipophilic nature or their hydrophilic nature.
35:47 for example, the two major classes immune hormones include the CTA Cola means
35:55 a weird word. It's like, don't know what Ac Cola is.
35:57 , you do CCO means are Norrin Epinephrine. You've heard of those kind
36:02 like maybe here, let me give their, their common names.
36:07 Have you heard of adrenaline? That's . All right. Nor ephrine is
36:13 cousin nor adrenaline. All right. if you're not hurting no nor
36:18 that's ok. All right. They do the same thing. Make your
36:21 beat faster and eyes bug out, you breathe harder. All right.
36:27 know that one. How about this ? You know, dopamine that one
36:30 heard about. All right, it's a neurotransmitter. Ok. So these
36:37 like hormones, right? That are in nature. All right. So
36:43 behave like peptide. So what type receptors? Do they bind membrane
36:50 Very good and everything that goes with . All right. Then we have
36:57 other type, which are the thyroid . All right. Now, thyroid
37:03 , um, maybe a little bit we talk about how it's made.
37:07 , most textbooks talk about how thyroid is made. And I think it
37:11 because it was the first hormone discovered it was made. And so everyone
37:14 excited and put it in textbooks and it got boring, but no one
37:17 took it out. All right. it's the only one we ever talk
37:20 how it's produced, right? But hormone is basically two tyrosine jammed together
37:25 then a whole bunch of iodine added the edges. You either get three
37:28 or four iodines. So you have trio uh thyronine, I pronounce
37:34 right? Thyronine. Yeah. And tetra io uh thyronine T three and
37:41 four, which is easier than trying remember. Trio yada yada yada,
37:46 ? But they behave like steroids. , amines are the weird ones.
37:52 the strange cousin and just, just . Oh yeah. Catomine behave like
37:59 . Thyroid hormone behaves like steroids even it's not a steroid so far.
38:05 you with me? Ok. Over we're good. Yeah. So it's
38:11 as it may sound like everything is little complicated here. I feel like
38:16 I go through this, I get kind of that blank. Stare,
38:18 it really is not that hard. again, you can do this kind
38:22 compare and contrast, which I have little thing here. It's like all
38:25 here. I got peptide here. had steroids. So what do they
38:29 ? Right. And you can just how is it made? Where is
38:31 stored? Is it stored? You , is it lipid soluble? You
38:36 how do I transport it? You , where is its receptor located mechanism
38:41 action? You get that honestly, can go into endocrinology uh and basically
38:47 through with just this knowledge right All right. So if you want
38:51 easy a after this class take end , I'm I'm not exaggerating. I
38:58 emails all the time just like fan one lecture piece of cake. It's
39:04 cool. This is just to show this mechanism of action for the
39:08 So here, what do we We have epinephrine dopamine. You can
39:11 G protein, G protein, what we doing? We're using G
39:16 but we're using a different pathway. this is the fossil lipase pathway versus
39:20 protein kinase A and cyclone P pathway far. So good. I mean
39:26 two terrible tour. Is that just ? Great. So what makes endocrinology
39:34 or complex is just how many things contradictory? And there's, there's things
39:41 make perfect sense and there's like, a second, but this contradicts
39:44 And I just want to kind of this kind of weird complexity here.
39:48 it's a little bit of me reading , but it's not, I'm just
39:50 to try to explain. So you think of a single endocrine gland,
39:53 single endocrine gland is not going to 1 to 1 ratio. So you
39:57 produce lots of hormones, you you're not limited to one hormone.
40:00 the anterior pituitary, for example, see is going to do six different
40:04 . So this is like a real gland. It's all it does is
40:07 hormone, all right. But you actually find a single hormone, not
40:11 limited to a single endocrine gland, may actually come from multiple endocrine
40:17 So I can't just make a list memorize everything. No, because there's
40:21 crossover. The example I have here the hypothalamus and the pancreas which produces
40:26 same hormones, somatostatin and from the or from where it's produced, it
40:32 has different ramifications. So for in the hypothalamus, somatostatin is a
40:37 hormone inhibitor. And while it's also growth hormone inhibitor from the pancreas,
40:42 its job is to do from the is to regulate digestion. So it
40:46 of does different things from different A single hormone can have more than
40:49 target cell. So here I have , insulin can act on a whole
40:53 of different cells, probably most of cells in your body. But the
40:56 ones are your muscle, your liver your fat. Uh, but you
40:59 also have, um, let's see . Oh, yeah, the rate
41:02 secretion is going to vary depending upon time of day or even the time
41:07 your cycle so on and so So it's not just his constituent
41:11 Um, we have circadian rhythm like . So guys, with regard to
41:16 testosterone, we have a daily pattern testosterone production. It goes up in
41:21 morning and then it kind of drops over the course of the day.
41:24 is kind of the same thing. have a low cortisol during the
41:27 but over the course of the it gets higher and cortisol deals with
41:31 , which kind of makes sense that body is just coping with all the
41:35 stress of the day. Um Menstrual is the obvious one that most people
41:40 familiar with. Uh estrogen starts builds up high, then drops off
41:44 then it's replaced by higher progesterone So this is just again, showing
41:48 a broader pattern of expression. Uh single target cell can be influenced by
41:53 than one hormone. So this is of the gas and the break type
41:57 of hormone regulation. Uh The two , I here, insulin glucagon,
42:02 you probably learned before insulin promotes uh the uptake of sugar and carbohydrates proteins
42:10 lipids in the cells where Glucagon promotes release of, of carbohydrates into the
42:16 to be delivered to the cells. , there's this, this uh opposite
42:21 that they have progesterone and estrogen have effects on uterine cells. Late deli
42:26 late in la or not de late in pregnancy. Um progesterone um
42:34 there to promote the pregnancy. in other words, to maintain
42:38 And so it kind of inhibits the the production of contractions during pregnancy late
42:46 . But at some point that baby's to get born and estrogen's job is
42:51 promote contractions. And so there's this between the two and really what they're
42:57 is they're cross regulating. I think may have this here. Um
43:00 actually I took it off, they regulate their own receptor, the opposites
43:05 . So as progesterone levels rise, suppress the presence of estrogen receptors.
43:10 when estrogen begins to produce, it suppressing progesterone receptors. And that's why
43:15 get this switch off late in pregnancy those contractions. Um Let's see,
43:22 depending on the circumstance and what, , what context you're referring to
43:27 A hormone can be a neurotransmitter or or it can be a hormone.
43:32 the classic one is Norine when it's in the blood stream, uh by
43:37 adrenal glands, it's called a But when you're talking about the sympathetic
43:41 system, it's acting as a And so we just refer it as
43:45 . Uh lastly here, uh we've already kind of alluded to this.
43:50 showed you kind of the, the picture like these are endocrine organs.
43:55 there are what are called classical endocrine because all they do is produce
44:00 they don't do anything else. But are organs that are considered endocrine that
44:06 multiple functions and endocrine is not even primary function. All right. So
44:12 can have that duality. So two here um for the endocrine anterior
44:19 we're gonna look at that in just moment. This is all it does
44:21 produce hormones, it doesn't do anything . All right. But the test
44:26 , for example, produces testosterone, that's not its primary function, its
44:31 function is to produce sperm. So two things while they're not both
44:38 one is it makes it, it's an endocrine organ because of the production
44:42 testosterone so far. OK. Those . So sometimes endocrinology becomes a little
44:49 just because of what you're looking at just because of these, there's some
44:53 in some of these things. You for some biology. Math. I
44:59 you there's no math on the test there's biology, math. OK.
45:04 three terms help us understand biology, , permissiveness, right? Synergism and
45:13 . And those words should already have little bit of meaning to you.
45:16 what I wanna do is I want kind of demonstrate this with regard to
45:20 hormones. And so up here on top, we have a chart and
45:24 below this nice little graph kind of these, uh these three things really
45:28 synergism and permissive. All right. , with regard to permissive, what
45:34 doing is you're saying, hey, is the effect that this first hormone
45:37 on the activity of the second All right. So it's allowing or
45:42 permission to allow that hormone to do . And so you can see here
45:46 this top chart, we have thyroid , thyroid hormone by itself. If
45:50 take a little tiny immature mouse and it with thyroid hormone, you're not
45:53 to watch its testes get all You're not gonna watch the ovaries grow
45:57 do anything. It's a very, boring injection. Nothing happens.
46:01 if you're a reproductive guy, all . But I can give them a
46:06 bunch of steroids and FSH and which are govern all the reproductive
46:10 And guess what happens? You get delayed activity. All right.
46:17 maybe these things don't really do Uh But if I give them thyroid
46:22 plus those steroids and FSH and LH get normal reproductive development. So,
46:30 hormone is permissive towards the steroids and gonadotropic hormones, you need to have
46:40 hormone to allow the other ones It's permissive. Does that make
46:44 Ok. Synergism. This is the map. All right, here you
46:49 see the effect of cortisol, the of gluco and the effect of epinephrine
46:53 blood glucose levels. So by cortisol, gluco and epinephrine don't do
46:57 whole bunch to raising blood glucose right? But if I take a
47:02 of glucose and epinephrine, I get significant increase in blood glucose. If
47:08 give all three, I get a response. So you see the effect
47:14 is not just additive, it's almost and this is why I call this
47:20 math in biology. One plus one not equal 21 plus one equals
47:28 See, yeah, that was a dad joke. I've been using that
47:34 a long time. It's 11. right. And that's what you're kind
47:38 seeing here. It's like I give little dose of this a little bit
47:40 that. I'd get a massive All right. That would be
47:45 They help each other in terms of response. It's more than additive,
47:51 would be where they are fighting against other. And this was that,
47:54 example I gave of progesterone and basically dueling it out to determine which
48:00 is going to be the one that uh going to dominate. All
48:04 because they're basically my expression down regulates just your expression but the expression of
48:10 receptor. So you don't get a , right. That's the idea.
48:16 right, it is the opposite of or synergistic. So the most important
48:28 of the body. Well, maybe don't know. That's not gonna be
48:33 question. What is the most important ? Unless it says, what is
48:37 Wayne's most important gland? All then you'd know that this is one
48:41 . All right. So we have pituitary going and I know this is
48:44 an anatomy class. So, part this is you using your imagination to
48:49 what this structure is if you've never or gone digging around in a
48:54 whether virtually or otherwise, because who's let you go digging around in the
49:00 , right? What we have is have this little tiny itsy bitsy structure
49:07 can see here's our brain right This little tiny, I can make
49:13 hand sit still well enough for that there. It just hangs down.
49:16 have this little tiny stock, it's called the stalk indium. And then
49:21 at the bottom of this is you this structure, this is the pituitary
49:25 . And if you were able to a hole through the top of your
49:28 cavity and through the top of your cavity, that's how you get to
49:32 . That's what we do to mice rats if we want to go extract
49:35 thing and it hangs just below the . All right. So this is
49:39 neural structure. Now, it's neural nature, but it has two parts
49:44 it. We have a part that glandular. So this is neuroepithelium.
49:49 it's neuro glandular tissue, the other , the posterior pituitary. So this
49:54 the front over here. See there's front of the brain over here.
49:58 is neural in nature. So it nervous tissue means it is made up
50:02 nerves. So that's the distinction between 21 is epithelium in nature. One
50:07 neural in nature. All right. , these structures produce hormones. Both
50:12 them do both the anterior and posterior . The anterior side is connected to
50:17 hypothalamus via a very, very small system. Now, a portal system
50:23 simply a capillary system that doesn't go an artery and a vein. It
50:28 between two little areas of the So you've probably heard of the hepatic
50:33 system. Have you heard of that ? The portal system? Basically,
50:37 blood from your stomach goes first to liver before it goes back to your
50:41 . It doesn't, it doesn't bypass that way. All the nutrients and
50:45 the poisons that you are eating from Cheetos and all the horrible things that
50:48 put in your body first, go your detox center before it goes on
50:53 your heart, right? So portal are, are basically moving between two
50:59 . And so that's what we have we have the hypothalamus and here's our
51:02 portal system, taking the blood directly the anterior pituitary. All right,
51:09 regard to the poster pituitary, it nervous tissue and really what it
51:13 is an extension of the hypothalamus. other words, we have up here
51:18 the hypothalamus, specific regions, the uh um um nucleus and I'm not
51:25 what the other one is called. is it? I don't have it
51:28 here. Um It's a super uh Chima and then the preoptic,
51:33 I was getting them confused. Um where you find the nuclei of the
51:39 that produce the hormones that are going be released from the posterior pituitary.
51:44 then the portion of the infant bum forms the posterior pituitary are the
51:51 So what you're seeing is the cell bodies are located located up in
51:55 hypothalamus and they extend down and their ends make up the posterior pituitary.
52:01 , hormones are made in the hypothalamus are released from the posterior pituitary.
52:09 we have two structures that produce different or release different hormones and they behave
52:14 different ways. The easiest one to at is just let's get the posterior
52:18 out of the way because it produces hormones of interest, vasopressin, also
52:22 as antidiuretic hormone. It's also abbreviated BP for um arginine Vasin and then
52:30 other one is Oxytocin. All And they're very closely related. The
52:35 is I think a single amino acid these two peptides. Now, as
52:38 mentioned, we have um these uh nuclei that are located in the
52:44 And up here in these nuclei, , for example, up here in
52:48 paraventricular nucleus, they don't all just a VP or uh or um uh
52:55 want to say a MP but a . All right. They don't just
52:59 that the, the nuclei that can one of either. All right.
53:04 you can make both hormones in the different regions, but you're only whatever
53:08 neuron is, is only going to whichever one it makes. All
53:12 So if you're a neuron, you only make one or the other,
53:15 you can live in either spot. makes sense. Ok. And so
53:19 it's gonna do is those axons travel and then when that neuron is signaled
53:24 in the hypothalamus to release, then release that hormone out into the bloodstream
53:29 off it goes and does its Oxytocin plays an important role in uh
53:34 muscle contraction. You're probably most familiar it with regard to smooth muscle,
53:40 of labor and delivery. But it plays an important role in milk
53:44 It plays an important role during female and male orgasm. But one of
53:49 most significant roles I think and something you should kind of take to the
53:52 with you is that it creates the bond between men and women after
54:01 Yeah, it's a love hormone. right. Let me just paint the
54:06 for you because I can see you falling asleep. And I'm trying to
54:08 you interested. When I say everyone's eyes usually pop up. All
54:13 . So man and woman have What does a man usually do after
54:19 ? Stereotype? I'm gonna stand up and until you guys have the courage
54:24 say it, what do they No, no, no,
54:30 After that, huh? She says . Sure. That's what we want
54:38 do. But what do we end doing? That's the word I'm looking
54:43 sleep. All right, guys fall . That's what Oxytocin does. It
54:47 guys to fall asleep right after sexual . What do women want to
54:56 What? Cuddle, cuddle? That's word I'm looking for is cuddle.
55:00 it does is you cuddle up, ? That's the bonding thing. And
55:04 you see how both these hormones work ? This hormone works differently in,
55:09 , in human, both male and to create a bond because we're trapped
55:14 we're, you know, and then like, oh yeah. All
55:20 You don't want to talk about It's gross and scary and embarrassing.
55:23 . All right. Woman gives birth a child, right? She's just
55:28 how much Oxytocin in her body to that to happen. Just go ahead
55:32 nod your head and say lots. ? And so the first thing they
55:35 is they take that baby and they it on the mother after she's given
55:39 and she sits there and holds it she's washing her body over and over
55:44 Oxytocin. That's why it's such a deal because it creates that child mother
55:49 as well. All right. Love . All right. Now, what
55:55 , what does, uh, vas do? Well, its job is
55:59 regulate your water salt balance, anti hormone diuresis. What's another fancy?
56:05 a non fancy word for diuresis? , ping is the word I'm looking
56:10 ? Yeah, I heard it. . So, anti peeing hormone,
56:16 what it does. It says when dehydrated instead of producing urine and peeing
56:19 that water, I want to hold to. What I'm gonna do is
56:21 gonna pull water back into my body prevent it from leaving. So,
56:26 to you making urine, it tries hold on to it. That's its
56:31 . All right. Now again, making this because they're peptides, you're
56:36 it up and that's when you release . When it's time to release the
56:41 pituitary is a little bit more As I said, it produces six
56:45 hormones. These hormones are primarily responsible metabolism for reproduction. And let's
56:51 what else do we have up Do I have it up here?
56:53 don't have a list up. It's , reproduction and growth are the,
56:57 the things I'm looking for? All . So we have two kinds of
57:03 . All right. The first word see up there, it looks like
57:06 is pronounced tropic because reasons. All . The other way you can see
57:11 , you can put a little H there between the P and the I
57:14 call it trophic. All right. kind of like a trophy but trophic
57:19 what these hormones do is they regulate hormones. Right. And so I
57:23 abbreviations up here, but don't there's a slide that has their
57:27 I'm just too lazy to write those . All right. So what we
57:30 is we have growth hormone, thyroid hormone. What do you think that
57:35 it stimulates the thyroid? Ok. making sure we're on the same
57:40 Adrenocorticotropic hormone, adrenal cortex, stimulating is basically what it does,
57:48 It adrenal corticotropic hormone. Then we follicle stimulating hormone. What do you
57:53 it stimulates follicles? Do you think the hair? Nope, not at
57:57 . It's actually ovarian follicles, which it horribly confusing if you don't know
58:01 an ovarian follicle is. And then have something called lutin hormone, which
58:04 even more confusing because it's named based on cells that turn yellow because
58:10 is saffron yellow. And so you cells that are white that turn bright
58:15 , they didn't know what it was . And now we know what it's
58:17 , but that's lutin hormone. FSH LHs are the two gonadotropins. They
58:23 on the gonads both in males and in very specific ways. The non
58:28 hormone up there is pr L known prolactin pro is four lac milk
58:38 at the end of any word is . So, for milk protein.
58:44 it, it promotes lactation. It's in couples with or couples with
58:48 In terms of breastfeeding, prolactin is to make the milk. Oxytocin is
58:52 ejecting the milk. All right. , these hormones, all right.
58:59 trophic hormones are typically regulated by hypothalamic . All right. What we were
59:05 to refer to as releasing hormones right , technically, these are also trophic
59:10 . But if I told you, trophic hormones are regulated by tropic
59:14 you'd be like. But, but , so it's easier just to call
59:17 releasing hormones and inhibiting hormones and let go on your merry way and figure
59:20 all out. Ok. So we regulating hormones up in the hypothalamus that
59:25 regulating hormones down in the anterior The pitu anterior pituitary hormones here are
59:31 regulating hormones. And so they're going be regulating something else downstream and then
59:36 thing that they're regulating, which is a hormone is going to come back
59:40 a feedback loop and regulate them as . We'll see this in just a
59:44 . So this is the big long . So I just kind of went
59:47 . All right. So here we control uh growth metabolism, reproduction,
59:54 ? The weird one of the, the bunch are pr and growth
59:58 They both have the gas in the , they have a releasing hormone and
60:01 inhibiting hormone. All right, all rest of them are just going to
60:04 what is called the classical hypothalamic Feedback loop hypothesis refers to the pituitary
60:13 . All right. And we'll see in a slide here. And so
60:16 all those functions, milk production. I mentioned, we're ignoring the immune
60:20 , regulating the hormones of the Thyroid stimulating hormone produces or tells the
60:26 to produce the thyroid hormone. Adrenal hormone is responsible for regulating the adrenal
60:33 . So, primarily the mineral but that's not the only things that
60:37 being regulated through there and then growth , everyone kind of think. Oh
60:41 , it plays a role in Yes. What it does, it
60:44 causes the reg or it regulates the of these hormones downstream called the insulin
60:50 growth factors. All right. Their name is the Somas. All
60:55 And that's what regulates whether or not cells are getting bigger or uh not
61:00 but just getting bigger or not. . So it works through its own
61:04 of hormones. This is just a to look at them to kind of
61:09 them. You know, here's here's the the hormones we're looking at
61:13 is what regulates them. So you how, how, how difficult this
61:17 , it's growth hormone releasing hormone, ? The inhibiting hormone is called growth
61:25 , inhibiting hormone. But we want be confusing. And so that's the
61:29 that I mentioned earlier. Stupid people things two things. What do you
61:36 that one is if this is thyroid hormone, what do you think that
61:40 is thyroid releasing, releasing hormone? . So these are the gonadotropins.
61:47 this is gonadotropin releasing hormone. Yeah. And then uh prolactin uh
61:56 downstream of dopamine, but we're not worry about that right now.
62:01 So here's the feedback loop. Remember said we have the gas in the
62:04 . That's uh prolactin and growth hormone the gas pedal on the brake
62:08 So the growth hormone releasing hormone growth inhibiting hormone dopamine acts as the inhibiting
62:13 . I can't remember what the prolactin is that promotes it. I i
62:20 gonna take a while and frankly, can't even remember if we know for
62:24 these are the feedback loops. You this. You've learned everything you need
62:28 know about endocrinology and you just go take the grade, get your a
62:31 on. OK. I'm just telling this. Now, it's, this
62:35 the easy stuff over here. On left side of the picture, you
62:38 see the basic pattern here. All , I'm gonna have my first
62:44 right? This would be the it's releasing a hormone that hormone acts
62:47 the second um uh tissue. This be the anterior pituitary that releases a
62:54 . You're going to get a feedback control that system. So when this
62:59 gets high, it turns us So it slows it down. So
63:02 your negative feedback loop. But in process, not only is it feeding
63:06 , but it acts on that third , that third tissue is going to
63:09 a hormone as well. All And so here is an example of
63:13 . This is using cortisol as the target. So up in the
63:18 we're producing corticotropic releasing hormone that's crhcrh on the anterior pituitary to cause the
63:25 of adrenal corticotropic hormone, adrenocorticotropic hormone on the adrenal cortex to produce
63:32 So there's your ABC down the All right. But AC th works
63:38 in a negative feedback fashion to down crh. Right. So I'm basically
63:44 up and down like this with when comes to uh uh crh and ac
63:51 when I make cortisol, cortisol feeds in a short loop back to the
63:57 . Hey, you made Cortisol, here. You don't need to make
64:00 more. So it down regulates ac that's what we see here,
64:05 What this is not showing is that also, well, it does,
64:09 there it is. So cortisol also all the way back up to the
64:12 and regulates in a long loop, up to the hypothalamus. All the
64:18 pituitary hormones do this type of Ok. If it is a tropic
64:25 , this pattern is repeated. if you're talking about thyroid hormone,
64:31 does the same thing. If you're about the androgens or the estrogens or
64:34 progestins. Same thing if you're talking the mineral corticoid and the glucocorticoids,
64:40 a glucocorticoid right there. Same All right. So this is a
64:46 that is repeated over and over So, if you learn the
64:49 you've already learned all the big Now, you just gotta learn what
64:54 of these little hormones do when it's to learn what those hormones are.
65:00 . So far, are you with ? Any questions about the endocrine system
65:06 we've taught it so far? I of see those looks of like,
65:12 not sure I know this stuff Are we good? Look, I
65:19 it's like we're in the middle of lecture or so. But I
65:22 is anything like I have no idea you just said. There are
65:25 weird words that came out of your . It might have been Greek.
65:28 could have been ancient Samarian. I'm certain. Yeah, this thing.
65:33 . So think about trying to control driving right? When you're, when
65:38 in heavy traffic, let's say you're allowed to use your brake,
65:42 You only have your gas pedal. when I push on your gas,
65:45 you push on your gas pedal, do you do? You go faster
65:47 slower? So how do you slow ? Take your foot off the gas
65:53 . So that's kind of what's going here. Your feedback loop is watching
65:57 speed of the traffic around you. . So you're like, oh,
66:00 car moved ahead of me and giving space so I can now accelerate,
66:05 ? Oh, now I'm going too . I might run into the back
66:07 the car. So, what do do? I take my foot
66:10 I decelerated. That's kind of what's on here. There is no break
66:14 this situation because we don't have that hormone. So the negative feedback loop
66:20 looking at the, looking at the . Crh is looking or is waiting
66:26 a signal to tell it when to producing A th how do I know
66:30 produced enough A when a CT shows and says I'm here. So it
66:35 I am the negative regulator, stop cr and so it slows it
66:39 It's really releasing. Crh is what should be saying. Same thing is
66:43 downstream. All right. How do know when to turn off? Ac
66:47 Well, when I have enough All right. Well, what else
66:50 cortisol do besides its activity? I'm gonna go all the way to
66:54 top and I'm gonna regulate the entire . That's that long loop. So
67:00 we refer to this as this is is referred to as a short
67:03 So this is a short loop, this going all the way back would
67:06 a longer long loop. There's also loops. I, I'm trying
67:11 it's like super short, so I it listed here. No,
67:16 there's even ones where there's things where in a micro loop, but we
67:19 , we're not gonna worry about micro . All right. But does that
67:22 of make more sense? Did were you explaining it? Make it
67:26 clear? Yeah. Ok. So got like 13 minutes to talk about
67:33 now, which is fine. We'll up. I usually start talking like
67:38 auctioneer here in a minute. All . So if there's no questions,
67:43 happy to entertain other questions about. , there we go. See.
67:46 we start getting them. Ok. was gonna change subjects. Let's just
67:49 , keep them in. Yeah. ahead. Tell me when. Thank
68:06 . Yeah. Yeah. OK. again, I understand why that's complicated
68:11 we don't have a frame of You, you haven't done anatomy in
68:14 nervous system yet to really kind of this. All right. So
68:17 I get that. All right. part of this is you're going to
68:19 it up as we go through the of this unit and, and
68:24 But let me just kind of describe . All right. So a neuron
68:26 a type of nervous cell, all , that is specifically has a cell
68:32 and then it has a region that receives information, then it has this
68:36 extension to send information. And at far end, it releases neurotransmitter
68:40 All right. Now these are going be uh uh endocrine nature. So
68:44 of releasing neurotransmitter, they're releasing hormone neuro hormone. So what this is
68:50 you is saying, look up here around in all these areas, those
68:55 where the cell bodies are. So cell that is responsible for making the
69:00 is not located down here. Like saw over here in the anterior
69:05 the cells that make up all those in the anterior pituitary are in the
69:09 pituitary. It's a glandular tissue. , these are little tiny epithelial cells
69:14 they're just releasing their materials over This is the the cell or the
69:21 terminal of that neuron way up So that neuron is making the hormone
69:27 it's sending it down and, and it up here. So when it
69:31 a signal up there, it will it from here. So that's one
69:34 the the major distinctions of this being tissue because it's a neuron doing the
69:40 . Not an epithelial cell. ma'am. And then I'll come back
69:43 see if while you Yeah. because because they're coming from neurons,
69:53 are technically a neuro hormone, So the two hormones from this
70:01 oxytocin love hormone, a DH water , the ones on this side,
70:07 are the trophic hormones being solely produced those glandular cells down here. How
70:11 we regulate those glandular cells? By hormones being released from the hypothalamus
70:18 the bloodstream that travel down and regulate . That's why we have that portal
70:23 in place. That kind of help . Yeah. So pick, pick
70:33 one you're gonna make. Are you make 88 or are you gonna make
70:37 love or water? All right. making love, love it.
70:45 So, you're making that all Now, choose where you wanna
70:48 You wanna live up in the paraventricular do you wanna live in the uh
70:53 or the uh super cosmetic nucleus? . Great. Now you live
70:59 but you can only make Oxytocin. right. Now, I'm gonna hang
71:05 there too. I live there, I've chosen to make a DH.
71:09 notice we live in the same but we make two different hormones and
71:12 can never change what you're making and can't change what I'm making. All
71:17 . So that's the idea is once neuron makes a specific hormone, that
71:22 what it's destined to make, but not limited. It's like,
71:26 you decided to start making Oxytocin. , now you have to live over
71:29 in the Super Kias. All It's where you're located can be either
71:34 those things now and I'm going down rabbit trail for this one. All
71:39 , because it's really not that But the reason that this probably has
71:46 the way it happens in humans is oxytocin and a DH, like I
71:50 , they're small peptides and they differ each other by a single amino
71:56 All right. In other words, look at the sequence, I think
71:58 is that uh in that uh arginine I mentioned in Vasin birds, they
72:07 have one and it is governing both . So it acts as that love
72:13 . So it's not a really strong hormone. It, but it acts
72:17 that fashion and it also plays a in regulating water, right? Other
72:24 have the same thing where it's like only one. So it governs those
72:29 . Humans are unique, not the organism that has it, but we're
72:32 of the unique ones that has some of mutation that created two genes and
72:37 one changed just enough. And so we have these two different gene or
72:41 different proteins doing two different things. kind of cool. That was the
72:45 trail. Any other questions? I spent my time looking in that
72:50 Any questions over here? Yeah. . Opportunity. Yeah. So there's
73:02 you what this is trying to show all the blue is trying to show
73:04 blood vessels there. So it's being into the blood. So we're gonna
73:09 this in a couple lectures. I remember where exactly. I think it's
73:13 unit two. there's a blood brain , but the pituitary gland is one
73:17 where that blood brain barrier is not stringent so you can release directly into
73:22 bloodstream. So, yeah. All . Oh, I'm sorry. Go
73:33 . No, no, no, , no, not anatomy class.
73:35 just mentioning it because it's kind of of these unique situations. Yeah.
73:43 If, if you do have to it, I'm not gonna say you
73:46 because it's almost like one of those where it feels like it's trivial to
73:49 . And again I teach a So sometimes I can't remember what I've
73:53 . It's, it'll be obvious, know, super optic. I
73:57 it's like the two nuclei that you'd the names of. Right? Or
74:00 you've seen because I don't talk about of their nuclear for a long
74:05 Ok. But I suspect that I ask you where it's from. I
74:13 I would because one, I'm lazy I use them a lot. All
74:17 . But generally speaking, when you're endocrinology, you go into the alphabet
74:20 because it's just easier. So, DH, it's like, ok,
74:25 , what an anti diuretic hormone? . Ok. Follicle stimulating hormone.
74:33 , that has the, it has gas and brake system. Yeah.
74:37 . From the anterior pituitary, you're see that other systems have weird things
74:42 that as well or behave like that well. So, for example,
74:46 glucagon behave with a gas are, basically act as a gas pedal and
74:50 . All right. But they also these negative feedback loops that kind of
74:54 in there as well. And so you do is the, the unique
74:57 about endocrinology is like, you learn two basic things and then you start
75:00 that they kind of work with each and it's just like, ok,
75:04 , I've learned this system now. one does it use? Uses
75:07 All right. All right. So we'll see what we can get
75:15 I mean, I got five minutes we're like what 700 pages, 700
75:19 behind. Let me see if I , what I can do here to
75:26 . At least maybe a couple of , some things you already know about
75:30 . You are, you are neutrally , you have an equal number of
75:34 negatives. So you're neutral, you're electric, you understand, opposites attract
75:39 ? Positive negative charges attract each Same charges, repel separating two charges
75:44 energy. You guys understand that right? So if I have two
75:49 that attract each other, it takes to separate them out, try to
75:54 a party of really, really hormone youth and you'll see quickly how it
76:01 a lot of work. Um The separator here is gonna be the plasma
76:09 and basically it serves as an All right. So that's the thing
76:12 separating out. So the insulator plasma , the environment through which these ions
76:17 gonna be moving. That's your That's the water, whether it be
76:21 or intracellular. All right. This where the text I know gets
76:27 All right. What we're really talking what I want to talk about here
76:30 basically membrane potential changes. All So what is the membrane potential?
76:35 this probably will be the slide that end on just because of how I
76:39 to explain this. All right, membrane potential is simply the separation of
76:45 charges, the positive and negative charges your body. OK. So when
76:51 talk about a membrane potential, you're talking about a charge on the
76:55 you're talking about the ions on either of that membrane being separated from each
77:00 and wanting to get next to each . The example I use and why
77:04 probably gonna stop here is I'm gonna , do you guys know um about
77:09 High school? You know where it ? It's over in River Oaks.
77:13 the rich kid high school. And next door is the other rich kid
77:16 school which is uh Episcopal High School they're both very large six a schools
77:22 Episcopal is and they're right next door each other. All right, and
77:25 separated by a little tiny chain link . OK. Now you can imagine
77:31 um Lamar that there are couples that formed in this school. Right.
77:36 gonna use heterosexual couples because opposites Right. So you got couples in
77:42 school and they give each other go , they walk down the hall and
77:44 hold each other hands and all that fun stuff that couples do.
77:48 But you can also imagine that there unmatched charges. In other words,
77:53 non couples, there's singles in the as well and the same thing is
77:57 be true over at Episcopal right I want you to imagine for a
78:01 that in that, in those two that they have an open campus lunch
78:08 they meet, they can have lunch on campus. They just can't leave
78:11 campus. And so Bell rings at time, everyone kind of storms out
78:15 the warm Houston, humid uh They go out and you know,
78:21 do the couples do? They hang with each other? Give each other
78:24 , go eyes and share each other's butter jelly sandwiches. Right. But
78:27 do the singles do? They kind walk out? Kind of sad.
78:32 . They got their bag of maybe a squishy banana and they walk
78:39 and they look, and they happen see across the chain link fence an
78:47 , right. Something that they're attracted . So what do they do?
78:52 migrate towards the fence? So sad number one and then on the other
78:59 of the fence is they see that and they go to the other side
79:05 they want to be together, but can't, why can't they be
79:08 Stupid fence, right. So that is imp hindering or blocking their ability
79:15 come together right now, if you it up, the number of singles
79:21 are sitting there across, looking at other going, I wish we could
79:25 together. Then what you're looking at is the difference between the number of
79:30 charges on one side, the number positive charges on the other side is
79:33 membrane difference. It's the potential Why? Well, basically it's potential
79:41 , right? The difference being the difference between the two sides. So
79:46 do we, how do we reduce potential energy? What do we need
79:49 do if we have a little tiny link fence, what do we need
79:53 do? Open up the gate? we open up the gate, then
79:57 can get flow and then we can those couples to match up and then
80:01 is gonna be hunky dory and life good and everyone's eating their squishy banana
80:05 now, that movement that we just is going to be current and that's
80:11 we're going to be kind of be with here. But what I wanted
80:14 to understand when you walk out of right now is the thing that we're
80:19 about are all those unmatched charges in picture down here, right? What
80:25 can see are these things hanging right? You can see these pairings
80:30 what would happen is these positive charges move over here and the unpaired negative
80:35 would move up here. And that's you're looking at when you're talking about
80:38 potentials are those unmatched charges. And trying to figure out how do I
80:43 across this barrier? Right. So we come back, we're going to
80:48 at what's responsible, which ions and we go about doing it. We're
80:52 to deal with the action potential and graded potential go to the football game
80:58 send.
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