VideoPoints

• ••• • •• • ••••• • •
BIOL 2302 Human Anatomy & Physiology II - 2302_lecture13_0309
Help Tour
© Distribution of this video is restricted by its owner
Transcript ×
Auto highlight
Font-size
00:04 All right, y'all. So what we're gonna do is we're gonna
00:09 in with the um the kidney and gonna continue with the process of how
00:16 making urine from the filtrate from the . All right. So remember what
00:22 were talking about on Tuesday, we about making the filtrate. And so
00:26 did we do? We took the plasma came through the aar arterial into
00:31 Gloria and then there was the pressure the glomeruli was strong enough or hard
00:39 or the net filtration pressure was strong to push fluid through the poto sites
00:46 through the epithelium and through that layer base membrane and get fluid into the
00:53 is called Bowman's capsule. OK. so now what we're going to do
00:59 we're going to take that fluid, has everything in it that was in
01:03 plasma except for the large stuff, ? So we don't have blood
01:09 we don't have large proteins, but have all this material in there that
01:13 the body wants and the body wants get rid of. So it's water
01:18 stuff minus the plasma proteins. And the next two steps that we're going
01:23 be looking at, looking at are re absorption and secretion. All
01:27 there's two different steps and they're going be occurring concurrently. And so what
01:32 going to do is we're taking the , which is step one, the
01:36 and we're now going to go through process of reabsorption and secretion. Now
01:42 do this, what we're going to to do is we're going to have
01:44 move materials from the tubule back into blood. And to do that,
01:49 means materials are going to have to through the cells that make up the
01:53 of the tubule, right? So have remember the proximal convoluted tubule,
01:58 have the loop of Henley and then also have the distal convoluted tubule before
02:02 get to the collecting duct or there's a collecting tubule in the collecting
02:06 . All right. And so the that materials move, and this is
02:10 a reminder is you can either move cells or you can move through
02:14 And so if you're moving between we refer to that as I should
02:17 turn this on is referred to as transport. So some materials will do
02:25 . They will, they will find way in between the cells move through
02:28 tight junctions and find their way out the, from the tubule back into
02:34 interstitial fluid. And then they'll work way back into the blood, other
02:39 can't do that. And so they to go pass through the cells through
02:42 process of what is called trans cellular , which means they go in through
02:47 tubular cell and then out through the side and if that's going to
02:50 you're going to need to have some of transport mechanism to allow that to
02:56 . Right. And so you should flashing back right now and thinking,
02:58 my goodness, he's going all the back to a MP one into that
03:02 unit for you took a P one we're starting to talk about those molecules
03:07 . And the answer is, that's kind of why we keep coming
03:11 to all this stuff. All So that's really what we're looking at
03:14 is we're going to be looking at through both those membranes and having the
03:20 materials there to allow for that movement occur. All right. So the
03:26 processes ire that we're gonna be looking absorption secretion. So to have this
03:34 , there needs to be something that or draws the materials one way or
03:38 other, right? And what we're do is we're gonna, I'm
03:42 we're gonna kind of walk through a of them and then I'm gonna tell
03:45 a little bit easy way to remember because it's something that I think we're
03:50 kind of familiar with that has nothing do with the kidney. All
03:54 But the idea here is we have have, if we're moving water,
03:58 gonna be a colloid pressure that's pulling towards where there's more colloid. You
04:04 what colloid means? It just means , right? So, where I
04:09 colloid, that means there's more stuff than there is water. And so
04:12 an osmotic gradient that draws water to the colloid is and it's just a
04:17 word for saying stuff. All So that's probably one of the ways
04:21 going to happen. So if you this higher solute con concentration, water
04:27 to where there's a higher solute con . And as a result of that
04:32 moving, there's going to be a flow of other materials because wherever there's
04:38 water solute follows. Does that kind make sense? All right now,
04:44 I said, I've got a little for you. Hopefully we'll pull it
04:47 together. All right. So what tubular reabsorption? What is tubular secretion
04:54 is the process by which the body back to it or the kidney returns
04:59 to the body, the things which wants or needs. All right,
05:04 talked about glucose, for example. right, glucose is something that your
05:08 doesn't want to get rid of it energy unprocessed, right? And you
05:14 hard to get that. Now you're hard is different than most organisms.
05:18 don't have to sit there and wait ambush like a mouse, right?
05:23 don't have to chase down a You just have to get on your
05:27 and doordash something. Right. So work is a little bit different but
05:31 still energy that's expended and energy that received and you don't want to just
05:36 away energy right in other word. me put it another way. If
05:41 had a pocket full of money and reached in and the money fell on
05:44 ground, would you just look at go? That's too much work to
05:46 pick that stuff up. No, would go and grab that. Even
05:50 it's a penny, you're like, my penny, right? And that's
05:53 of the same thing is that your is saying that is stuff that I
05:57 need and I don't want to get of it. It needs to come
06:01 . And so that's what Rebs is do, right? So anything that
06:06 body wants, it's gonna get, you don't have a reabsorptive ability to
06:10 something in, then your body doesn't need it. Ok? The last
06:15 is, um, uh, oh , the amount needed is gonna be
06:23 a function of those, that property I just said that, you
06:27 it has to do with your hydration and the presence of that material.
06:31 right. And so, for there are some things that your body
06:35 reabsorb, but if it already has much of it. It's not going
06:38 reabsorb it because it's got to follow rules by which reabsorption occurs. All
06:44 . And so really what we're talking about is water and ions. And
06:49 we'll get to that in just a . All right. Now, couple
06:54 things, the rate at which you transport something is going to be
06:57 It's gonna be dependent upon how many these channels or carriers that you have
07:03 . Which kind of makes sense. I'm looking around the room and I
07:07 walking in, how many doors do have in this room? There's 1212
07:14 then there's four in the back if think about it, right? So
07:18 many people can move in and out this room at any given time?
07:21 rate if each door represents one person per attempt. So we can move
07:28 people out and anything beyond that you're to start running into trouble,
07:33 So the rate at which we can people out is going to be based
07:37 how many doors we have. So we want to increase the rate at
07:39 we move people out of this what do we have to do?
07:42 have to add more doors. All . So transport ma maximum is the
07:48 fastest rate at which you can move from the tubular fluid out into that
07:54 space. It's how quickly we can that material. The renal threshold is
08:00 how much can be carried in the . Um Or let's see,
08:05 the point where you start exceeding the maximum. So, um for
08:14 um there is a finite amount of that you can have in your
08:20 All right. So glucose, like said, is an energy that we
08:25 hasn't been processed yet. But if are diabetic, for example, you
08:30 put glucose into your cells as well you should. And so what ends
08:36 happening is that the blood glucose levels to rise and rise and rise and
08:40 and eventually what happens is, is rate at which we re absorb that
08:46 is superseded by the amount that's found the blood. And so it stays
08:51 the urine. You know, the way how they used to discover and
08:55 out if you had diabetes. That's . Actually, they would, they
09:00 check the urine and it's even grosser that because the doctor would stick his
09:04 into the urine and taste the And if the urine was sweet,
09:11 had sugar in your uh in your and that's how they knew it.
09:16 Doesn't medicine sound fun now. just wait. All right. So
09:22 , that is the what when we about renal threshold, it's basically that
09:26 where the process of moving materials back the blood is exceeded by the amount
09:32 already in the blood. So you can't filter it fast enough. I
09:35 , it's being filtered but you're not it fast enough. All right.
09:39 , threshold maximum is the rate, fastest rate, which you can reabsored
09:44 amount that's in the blood. So just stays in the urine. All
09:51 . So what type of substances we ? Well, we have some,
09:55 substances that are going to be completely . All right, under normal
09:59 we're not talking pathologies. So these things that you don't find in the
10:03 normally. All right. Um So is typically the, the reabsorption is
10:08 to take place in the proximal convoluted . So it's kind of this easy
10:12 is remember what we said is when look at this, at the
10:15 it's a tube. And so you say, well, what's going
10:17 Well, filtration is taking place at front end of the tube. That's
10:21 Bowman's capsule between the gloss and Boman . So when I go in the
10:26 convoluted tubule, that's the first place we're going to start seeing reabsorption and
10:31 is going to be a whole bunch different things. But we have some
10:34 that are going to be completely And typically these are those things that
10:38 nutrients and those things which are plasma that have escaped through. All
10:42 And these would be very, very ones. So, in terms of
10:45 , we're talking about glucose. We're about amino acids, we're talking about
10:48 sugars like lactate. Um These things small and your body wants them.
10:53 in order to get them back in body, there has to be some
10:56 of transport mechanism that picks it up the filtrate and says you go back
11:01 the interstitial fluid so that you can back to the blood. And this
11:05 also going to be true for the plasm proteins. Um The difference
11:09 is we don't have um carriers because things are a little bit larger.
11:14 you're going to use a process of . So again, you just,
11:19 have receptors or you're taking samples of the filtrate, taking into a
11:24 , the vesicle moves around goes and it go off on the other side
11:28 the cell. All right. what's gonna usually happen is you're gonna
11:33 up those little tiny proteins and well, I, I'm not gonna
11:38 the actual protein. What I'm gonna is I'm gonna break it down.
11:41 so you get more amino acids and can make more of the plasma
11:45 but I'm not gonna let them leak because that is something that I can
11:48 to build other things or I can for energy. You do know amino
11:53 we use for energy, right? , ketones bodies. All right,
11:57 worry about them. All right. how do we do the uh
12:03 Well, most of the time, we're using is a co transport
12:06 All right. And again, this way back to a MP one way
12:09 at the beginning of the semester. we talked about these co transporters where
12:14 have sodium and what sort of nutrients interested in binding together. So the
12:19 wants to be in the cell down concentration gradient, glucose or amino acids
12:26 go into the cell because there's too of it. So there's no no
12:29 other than by expending energy. So use a co transport which is secondary
12:35 transport, meaning it doesn't use energy . So they bind to a receptor
12:40 the same time or a carrier at same time when both of them are
12:44 , then that carrier changes shape sodium in the glucose goes in or the
12:49 goes in and the amino acid goes . All right. And then on
12:53 other side, we may have a that allows that material to leak out
12:56 the cell down its concentration gradient. then sodium needs to be pumped to
13:01 to the other side. All So that's where the energy comes from
13:05 from that pump on the other All right. So from moving from
13:11 loin lommen refers to the inside of kidney. That's how we get into
13:14 tubular cell. And from the tubular , it's that passive process. All
13:20 . Again, I'm gonna make this simpler in just a moment. I
13:25 . Ok. And this is about it's gonna happen. All right.
13:34 then there's other things that we're going reabsorb, lots and lots of
13:37 So here's just kind of a partial . Water is something that we're going
13:40 reabsorb, but these things are gonna absorbed through a regulated process. In
13:45 words, it's gonna be based on . So if we have a lot
13:48 salt in our body, we're not to absorb all the salt. All
13:51 , if we have too much we're not going to re absorb all
13:54 water because that doesn't make sense. body wants to get rid of some
13:58 these things depending upon the conditions that in our body at any particular given
14:03 , right? So there's going to regulated mechanisms and the key thing in
14:07 of this is this statement right This last little bit, right?
14:12 is the thing that plays a major or a pivotal role in the reabsorption
14:18 all the substances. Are you ready the time out ready for the story
14:23 help you understand all this stuff. guys remember high school and high school
14:28 . Yeah. Do you remember That one cool gal. That one
14:32 girl. She's some of you might of her as the mean girl.
14:35 of you might have been that right? And she had the perfect
14:40 and the perfect boyfriend and the perfect were always walking around the high school
14:44 hands, doing everything together. Do you remember them? Right.
14:48 one went, the other one Whatever class one took, the other
14:51 did whatever, anything they did was coolest thing ever. So everyone hung
14:55 with them and so they had their , didn't they? And there was
14:59 of them, usually the guy, guy who was the friend in,
15:04 in the friend zone with the right? And you all knew who
15:07 was because you're like, dude, never gonna hook up with her.
15:11 he was there, he was there that girl just in case the bad
15:15 that guy broke up because he really right for the the the guy was
15:21 . But she had all her girlfriends followed along. And so it was
15:25 grand group of people and movies have written about this stuff, but every
15:30 school had something like this. Are all familiar with this idea? All
15:37 . Sodium is that girl? Is that guy that he's hooked up
15:44 that's hooked up with that girl. sodium goes water follows who wants to
15:49 up with sodium? It's an easy . Chlorine, right? Sodium and
15:58 man, they, they match, perfect for each other, right?
16:01 no, no, no sodium when is around dissociates and wants to hang
16:04 with water. So wherever sodium you know, water is gonna naturally
16:08 . And then because of osmotic chlorine is gonna follow because,
16:13 I got to hang out with the . I gotta hang now with
16:16 So it's gonna follow. And whenever goes someplace what you've done now is
16:21 created an osmotic gradient that drives the of all the other stuff,
16:26 So if water goes, there's more over here than there was before.
16:29 potassium goes, there's more water over . Bicarbonate goes, there's more water
16:33 here. Calcium goes, you name ion, it follows water. Do
16:38 see the process here? So, this is the statement you need to
16:43 ingrain in your brain wherever sodium water falls, wherever water goes,
16:48 else falls based on osmotic considerations. But doctor Wayne, you said glucose
16:53 sodium move together. That's right because is the cool girl and who wants
16:59 hang out with the cool girl? . So glucose moves with sodium amino
17:05 , move with sodium, right? moves based on those two things really
17:12 on sodium. But it's wherever sodium water follows. OK. That was
17:17 end of the lecture. Go That's basically what the rest of this
17:21 is all about. If you understand concept. Sodium in water. I
17:25 . Let's see if people actually get . We're gonna see if this is
17:29 , right? But if you understand soda goes, water follows. Then
17:33 we gotta do is figure out where is going and then we're going to
17:36 where everything else moves. All this is the beauty of kind of
17:41 that step back and looking at the picture rather than trying to memorize a
17:44 bunch of little tiny things because we see stuff like this. So where
17:49 sodium reabsorbed? Where does sodium It's a regulated molecule. So it
17:53 some place. Now, I want to think about all the sodium in
17:56 body. All right, the stuff in the blood that's circulating around,
18:00 ? It's going to be filtered. of that sodium, if 100% of
18:04 sodium is being filtered, 65% of is reabsorbed back through the proximal convoluted
18:11 . All right. So you can here why reabsorption is such a big
18:15 at the proximal convoluted tu because so of the sodium that is being filtered
18:20 the through the filtrate is is moving into the body. All right.
18:25 so these are the ones where we , hey, when we're talking about
18:29 of all the other stuff, this where it's happening. So sodium goes
18:34 falls wherever water goes because of osmotic , all the other stuff go.
18:39 that doesn't mean all of the sodium being absorbed here. You can see
18:42 here on the slide that that filtrate down through the loop of Henley and
18:46 the loop of Henley, 25% of stuff is being followed. And this
18:50 the part that plays a major role the concentration of your urine. And
18:55 going to spend the last half of class talking about this and how the
18:59 of Henley works. All right. then A small portion of your
19:06 about 10% is going to be reabsorbed the distal convoluted tubule in a highly
19:12 fashion. You've probably heard at some in your life that salt is bad
19:17 . You don't eat salt. It you high blood pressure. Have you
19:20 that? Right? It, it's not 100% true. There is
19:24 relationship and we've just figured out what relationship is. You mean wherever sodium
19:28 , water follows. Yes, that true. But what we have is
19:33 we call a sodium load in our . So that's not the, uh
19:38 the amount of salt you put in body. So, only 10% of
19:42 salt that goes in your body is to be regulated in this fashion and
19:45 that role in blood pressure. The 90% is there being reabsorbed naturally And
19:56 playing a role in adjusting your urine . So it's only that small,
20:02 10% that plays a role in, being regulated to determine whether or not
20:08 need to put salt in your body you need to excrete it into your
20:13 or secrete it into the, into filtrate. So it can be excreted
20:16 with the urine. OK. disco tubule is the regulated stuff.
20:22 right. So you can see it there regulating extracellular fluid volume when you
20:28 that or see that you should think pressure. Ok. So very,
20:32 small portion and that's based on your . So, if I have too
20:37 salt in my body, my body to get rid of it, but
20:40 wants to maintain a certain amount of in the body for the other
20:46 All right. Now, how does get absorbed? All right.
20:50 in the prom convoluted tubule, we channels. All right. That's kind
20:54 easy. So I've got channels that me to move down my concentration
21:00 So remember I try to keep low inside cells. So sodium moves from
21:04 channel or from the loin and from filtrate through the channel into the
21:08 And then on the other side, have a pump that sits there and
21:11 sodium, I want you out of cell. So it pumps it out
21:13 the um into the interstitial fluid, will then find its way to the
21:19 . And at the same time, pumping in potassium and so the potassium
21:24 going into the cell and I'm going be able to use that for other
21:27 as well. All right. So is how I'm moving sodium. The
21:31 way I'm moving sodium is I have cot transporters. I got sodium glucose
21:36 . I got sodium amino acid And so because of that low concentration
21:41 the cell, sodium wants to go and it brings along its partner glucose
21:46 the amino acids. And that's how move the glucose and amino acids back
21:51 the body. So the movement is this direction. All right, that's
21:58 I'm getting sodium reabsorbed. Now in distal convoluted tubule. This is that
22:04 . So notice I'm skipping over the of Hindley right now. All
22:08 because I want to put that all . So here, the more salt
22:12 put in your body, the more goes into your body, the less
22:16 you have in your body, the the water stays in the filtrate.
22:20 . So far you're all with right? OK. If the water
22:23 staying in the filtrate, that means peeing it out. That means your
22:26 is more water like. But when become dehydrated, what does your body
22:32 ? It wants the water. It want you to go and find
22:36 It already has water. I just want to let it go out into
22:39 bathroom. And so what your body is it uses hormones to adjust how
22:46 water is going. So one, things I can introduce pota sodium potassium
22:53 into the cells. In which now I'm pumping sodium back into the
22:59 , right? And wherever sodium goes follows. All right. So that's
23:04 way. And how do I do ? Well, that's gonna be through
23:09 . Aldosterone is a hormone that's produced the adrenal cortex, which we'll get
23:14 a little bit later. And what does, it says, hey,
23:19 over here in the distal convoluted I want you to put those channels
23:22 those pumps in place. So we move the sodium and then the water
23:25 follow in. And so what happens I move sodium into the body and
23:29 means the water is going to And that means I'm retaining water rather
23:33 letting it leave my body. The hormones at atrial retic peptide. This
23:39 the opposite effect. What it does it blocks or inhibits Aldo release.
23:44 I block that release, then sodium going to stay in the filtrate.
23:50 because sodium stays in the filtrate, stays in the filtrate and water leaves
23:54 body. Now, we've already learned these two hormones when we talked about
23:58 A A S when we talked about pressure. All right. So how
24:02 were cause blood pressure to go up Aldo and blood pressure to go down
24:07 by altering the water in which way going, is it going to the
24:12 or is it being removed or allowed enter back into circulation. So you
24:20 how there's a connection between all these . OK. So far so good
24:26 sodium reabsorption. I like the one . Yeah. Yeah, I got
24:30 . Wherever sodium goes waterfall is. mark. That's telling you you got
24:35 you're good to go. All OK. If you ever forget,
24:38 like, oh my goodness, I . OK. They just got to
24:40 of that one little thing and then rest of it should kind of fall
24:43 place. All right. Well, about water rebs sop? Well,
24:48 already said wherever sodium goes water So this is going to be osmotic
24:53 if I increase my solute out in interstitial space and in the blood water
24:59 going to move from the filtrate to interstitial fluid in the blood.
25:04 how do I increase my solute Well, it follows sodium. That's
25:08 solute. All right. So here pathway can be through the, between
25:16 cells. But the way to get moving really, really quickly is to
25:20 aquaporin, which are just fancy water . All right. They actually play
25:25 kinds of roles in the body. the primary role aquaporin even tells you
25:29 the name aqua water pourin. Ho I N is protein. So it's
25:34 water hole or a water channel. , in the proximal convoluted tubule,
25:39 aqua pons are always there and they're available so that water can follow the
25:43 in the distal convoluted tubule. We describe what happens. We pump,
25:48 the pumps in place. So the goes right. But if water can't
25:52 , we need to introduce aqua And so here we're gonna introduce um
25:56 uh aqua pons because of a different that suppress in which goes with by
26:02 name is anti diuretic hormone. All . And all this does is,
26:07 says, hey, I'm going to the aqua porns in place when it's
26:10 and when a DH is not I'm gonna remove the aqua porns.
26:14 water is either going to be able leak out of the, out of
26:17 filtrate or it's going to stay in filtrate depending upon the needs. So
26:23 , Aldora and Ad are working in to allow for water to move with
26:31 . These terms, you may see water reabsorption, facultative water re
26:37 It just refers to the presence of aquaporin. Obligatory means I'm obliged to
26:44 , right? If you're obliged to something, what does it mean?
26:47 have to do it? All So wherever sodium goes, water naturally
26:51 . So if I have an I have to follow, I'm obliged
26:56 do so. Facultative means there is facilitation, I'm being allowed to
27:03 OK. And so in this this will be the distal convoluted tubule
27:08 water, wants to follow salt, it can't do so unless I put
27:12 aquaporin in place. OK. So when you see those terms, that's
27:17 it means. So, proximal convoluted , obligatory facultative in the distal convoluted
27:28 . So just as a reminder, is vasopressin, it is antidiuretic
27:34 Um I won't go there. Um basically when you have low water in
27:39 blood. In other words, as levels rise and your water level is
27:43 , that's going to stimulate the production vas supress. It's stimulated in the
27:48 and it's released from the anterior or posterior pituitary gland, not the anterior
27:55 . And then it goes in And what it does is it introduces
27:59 binds to those tubular cells and causes porns. Two things aquaporin to be
28:05 to the surface because they're already there bound up to two. So
28:11 it's like you don't have to wait them to be made, they're already
28:13 . You're just telling the cell put in so that you can start moving
28:17 . And then it will also tell cell, hey, start producing more
28:20 these. So that, that's basically effect. All right. Now,
28:28 slide can be kind of confusing and not saying that it is confused.
28:31 just kind of because there's two things are being stated in this slide.
28:35 talking about reabsorption and secretion on this . All right. So it says
28:42 , secrete. So where it says , that means I'm secreting, what
28:46 secretion which direction if reabsorption goes into blood secretion would be going out back
28:53 the filtrate. OK. So when dealing with a potassium, potassium is
29:00 in different directions depending upon where you . So, in the proximal convoluted
29:05 , you're doing reabsorption. All you're following water. So where sodium
29:09 , water follows wherever water goes, other ions are following as well.
29:13 right, proximal convolute tubules easy. right, when you get down to
29:18 nephronic loop, you're still reabsorbing. . So we're just, so you're
29:23 again, we're, we're dealing with a bit. But when you get
29:27 here to the distal convoluted tubule and get to the collecting tubules. Now
29:31 dealing with secretion. Ok? So I am reabsorbing sodium, I am
29:39 either a channel in the distal convoluted or I am introducing in response to
29:46 sodium, potassium pumps, sodium is reabsorbed but potassium is being secreted based
29:55 those pumps. Ok. So in presence of aldosterone, I'm increasing the
30:01 of potassium secretion. Ok. So just one of those little things you
30:07 to understand if I understand mechanism, understand direction. So just a convoluted
30:14 aldosterone introduces sodium. Potassium A T S pumps, sodium is being
30:20 So water can follow, but potassium being secreted as a result of that
30:26 . All right. Now, this happening inside the type A inter or
30:31 sorry, it's not in the inter , they're constantly reabsorbing. So,
30:36 we're doing is we're modifying reabsorption by aldosterone. We're now secreting more than
30:45 are reabsorbing. But generally speaking, direction does sodium go or?
30:53 Potassium go. It follows water. does calcium go? It should follow
31:02 . What does phosphate do? It follow water. All right.
31:07 generally speaking, what we're doing here we're, what we're, what we're
31:11 is um calcium and phosphate is primarily up as a salt in your
31:18 So for those of you who took MP one, remember we spend all
31:21 time talking about bones, bones, and how they're not dead tissue that
31:25 play a role as being a calcium . And the way that we make
31:28 salts is calcium and phosphate. And when we need to circulate calcium,
31:33 break down bones and that means we're release both calcium and phosphate together and
31:37 stay disassociated in the blood. when you circulate that blood through the
31:44 , 6% of that calcium is going be filtered and about 90 95% of
31:48 phosphate is going to be filtered and wants to come together and hang out
31:52 they're attracted to each other and they salts and that's not a good
31:56 Um What we want to do really is we want to keep the calcium
32:00 the body because we can get phosphate anywhere. Phosphate, everything we eat
32:04 phosphate in it, right? Anything has nucleic acid, which means everything
32:09 consume phosphate, right? So, is an easy thing to access.
32:15 . Seems a lot harder to come . How many of you guys like
32:17 eat bones? No. Uh, here like to eat seashells. How
32:23 of you guys take calcium supplements, in your vitamins when you eat your
32:27 ? Yeah. So that's where your comes from, ground up bones and
32:31 , from seashells. Hm. It's , you don't know it because it's
32:36 washed and ground down in a little and you don't know better. All
32:40 . But that's where it comes Calcium is, that's an easy access
32:45 . And if you weren't getting it that, you'd be getting it from
32:48 , that's the other place we get from. You know, when you
32:50 of chalk, not the, the you write with before it's processed to
32:54 stuff you write with, it's taken of the ground and then it's isolated
32:58 compressed into a little tiny, little that we write with. Hm.
33:05 that calcium is valuable, right? makes strong bones. So we want
33:11 hold on to that. And so have a hormone, we'll probably talk
33:15 this a little bit later when we about the endocrine system and it's parathyroid
33:21 . I may not talk about it because I'm talking about it now.
33:24 right, parathyroid hormone comes from a tiny uh structure called the parathyroid
33:33 which is found on the back of thyroid or where's my thyroid?
33:37 the thyroid is this butterfly or bow looking gland that sits right here and
33:42 see this big old structures like that's big. Well, what is
33:45 parathyroid while you flip it around? like four little dots, one on
33:48 wing of the butterfly. And it's , OK, that's the parathyroid and
33:53 job is to help us to re calcium. And so one of the
33:59 that it acts is here on the and what it does, it
34:03 hey, um let's start reabsorbing calcium here in the distal convoluted tubule.
34:10 that puts calcium in the body which that we so that we can retain
34:14 . But the other thing that it , it says, hey, um
34:16 can go ahead and let that phosphate because I'll be able to get some
34:20 from my diet just simply eating I can get phosphate. And that's
34:25 of weird sounding but it's true. right. So this is how we
34:32 the calcium in our blood. There's that's one of three ways. And
34:37 when we talk about calcium regulation, is one of the three ways that
34:42 do that. So before I go , does this movement or regulation of
34:54 make sense wherever sodium goes water All right. And then I've got
35:02 things that can regulate and kind of that, but calcium moves back in
35:06 body. Not because of anything other that water has moved there.
35:11 I'm allowing it because of the presence the, uh, the parathyroid
35:16 All right. That makes sense. . It naturally wants to be reabsorbed
35:22 in the distal convoluted tubule where I a secretion mechanism. All right.
35:27 , the little exceptions are the things you have to understand. Now,
35:33 don't like to spend a lot of talking about uh buffering. Um because
35:38 buffering system is, is a little complex. It deals with the
35:41 it deals with the lungs. Have ever just sighed randomly? Just,
35:48 you done that? Yeah, that's of the buffering system that's removing carbon
35:53 so that you move more carbon, moving more carbon dioxide out. And
35:58 do that, I have to convert back into carbon dioxide. Remember we
36:03 about that when we talked about the , right? So that's part of
36:07 system. And I said we're not talk about that. All right.
36:10 bicarbonate is one of the major buffers the body. It actually out numbers
36:16 number of protons, something like 60 1. And so every time you
36:20 another proton on the blood, it shifts the P H towards um uh
36:29 . All right. So by carbonate the most part can be freely filtered
36:34 we have so much of it, just kind of there. And so
36:36 can kind of get rid of And that's one of the other ways
36:39 get rid of carbon dioxide. All . But protons primarily stay in the
36:45 . All right. So where do see this reabsorption? Most of it's
36:48 to be done in the proximal convoluted . So, if I asked you
36:51 question right now or this was a I had, what role does the
36:55 convoluted tubule play in the kidney? would you say it plays a
36:58 What would you, what do you the answer is gonna be absorption and
37:02 you're, you're starting to see. , great. All right. There's
37:07 that's gonna be reabsorbed in the nephronic . All right. But you can
37:11 of see that we're really dealing with um uh this idea of we're going
37:16 reabsorb materials uh through these two Now, what we, we absorb
37:23 what we secrete is gonna be dependent the state in which our blood is
37:27 found. All right. So when blood is more acidic than normal,
37:33 typically, this will happen if you a high diet in proteins. All
37:38 , because proteins basically uh shed off protons pretty easily. This is when
37:44 type a interrelated cells become very We said a for acid, that's
37:48 , really easy. And so what gonna do is we're gonna take those
37:52 and we're gonna start shedding them off out of the body. All
37:56 So the protons are picked up, use a pump system to do
38:00 and what you're doing is you take proton, you move it out and
38:04 any of the bicarbonate, you're going actually move back into the cell and
38:07 it. And so in doing so getting rid of the acid and you're
38:11 base back into the blood. Pretty . When you're talking about an alkaline
38:17 right here, you're just going to the opposite and it's the type
38:21 all right. So what they do they pick up protons and they're
38:24 OK, I'm gonna, instead of protons staying in the filtrate, what
38:27 gonna do is I'm gonna move them into the blood and I'm gonna pick
38:30 bicarbonate and I'm gonna shed it and it into the filtrate so I can
38:34 pee it on out. And so is how your body, the other
38:38 , one of the other mechanisms that body uses to maintain proper P H
38:42 the blood. That's basically all I to say about it. I don't
38:47 to make it any more complicated than . And like I said, the
38:51 play a major role as well and a lot more to it than
38:55 But I want you to understand those types of cells is that pretty
39:00 A for acid B for base. do the A cells turn on when
39:04 P H drops? When do my cells turn on when my P H
39:09 ? OK. And if that didn't sense P H, when it
39:13 it's acidic. Ready for the Weird you guys have a slow friend,
39:23 know that person that you can tell joke to and they stare at you
39:26 about 20 minutes and then they start . Yeah. Ok. That's your
39:32 right. So, in that big of friends, right? We got
39:35 cool girl. We got the cool , we got their friends, we
39:38 the, the, the guy in friend zone and then they also got
39:42 guy, right? The slow you know, still part of the
39:48 in, in, in all the . He's like the jock, the
39:51 jock. That's like dumber than a of rocks, you know, but
39:54 really big and he's the one that his head through the windows. And
39:59 right. You guys didn't watch the movie. So, you know,
40:01 didn't get revenge of the nerds and you're better off dead and stuff
40:05 that. Oh, I've got a if you need a bunch of movies
40:09 watch. All right. So is that. Now we get rid of
40:16 waste. Uh We have, nitrogenous waste exists in like three different
40:21 , right? And today I can the third one and I thought I
40:24 it on Tuesday, but I wasn't far off. All right. So
40:28 have urea, urea is what happens we break down proteins. And so
40:32 is a byproduct of amino acid metabolism protein metabolism, right? So,
40:38 your liver is doing and then you uric acid, uric acid is breaking
40:44 DNA and RNA molecules. So when you get down to those nitrogenous
40:49 , that's how you're getting rid of that nitrogen, nitrogenous waste through
40:55 nucleic acids. And the third type muscle metabolism, muscles use creatine.
41:02 then when you break it down, becomes craine. And that's the nitrogen
41:05 . That's how we, we take and we get rid of that as
41:08 . So those are the three ways we get rid of it, but
41:10 want to focus in on the first . Urea. All right.
41:14 when I said urea is slow, I mean is, is that its
41:17 of reabsorption is slower than the rate reabsorption of the other material. If
41:22 took a sample of your body, , any of the fluids, we'd
41:26 that you have urea throughout your entire all the time. All right.
41:30 it, it, it plays a in determining your os um your osmolarity
41:37 your body. So, just like salt everywhere, there's urea everywhere,
41:41 we're trying to get rid of It's not something we want to have
41:44 up because it can be dangerous or to us. But, because we
41:49 it in this form of urea, actually a lot safer than say
41:53 Would you agree with that? Ammonia pretty nasty stuff. Yeah. All
41:57 . So, this is what we're is we're using that. Now,
42:01 stuff is freely filtered and so when , when the blood passes through,
42:05 picking up the same portion. So portion of the uria that's passing through
42:11 filtrate or in the blood is coming the filtrate, but then it's being
42:15 and it's about 50% of the filtrate the urea that's in the filtrate is
42:20 to be reabsorbed. So let's just I had 10 molecules of your ear
42:23 pass from the blood to the Then through, in the proximal convoluted
42:28 , five of them go back into body and then your body says,
42:33 a second. Um um I'm trying get rid of this stuff. And
42:36 what it does is it picks up , that five and it moves it
42:41 in, in the loop of Henley , get rid of all this
42:44 So when the flu filtrate is going through the loop of Henle, I'm
42:48 up to 100% of the filtered. now I have 10 molecules back in
42:53 as an example. But then because osmotic considerations, urea is still trying
42:58 go back into the body. And again, it slowly moves back
43:04 Now, while we don't filter 100% the urea or, or secret or
43:12 me, excrete 100% of the, urea that we filtered. We're still
43:17 rid of excess urea. So by time you get down here to the
43:22 duct, You've reabsorbed 50%, So if you started off with 100%
43:29 to 50%, you're back to you're still getting rid of 50% of
43:34 Urea. And so you're getting rid excess stuff. But it's because it's
43:41 being attracted to the water that's returning into the body, it's moving with
43:48 . So it's a little bit It's not 100%, but it's good
43:53 does that makes sense. OK? it's not the only one there.
43:58 acid and Craine are doing similar but it's not like is, is
44:04 and that's why we bring it Ok. So we've covered a lot
44:11 different things, right? But we sum it up in that one little
44:18 wherever sodium goes, water follows and else kind of goes with that.
44:23 there's some things that we want to rid of faster than, than the
44:30 filtration process. And this is where comes into place. And so what
44:35 have is we have a system that's more complex than we're going to explain
44:43 in essence, what it is is the proximal convoluted tubule. There are
44:47 molecules that recognize metabolites of different processes get rid of things that we don't
44:56 around. All right. So let just try to explain this using
45:00 for example, or not like not , drugs, bad drugs, shame
45:05 you drugs, but like medications. right. How have you guys taken
45:12 ? If you take two ibuprofen? the next time you can take two
45:17 ? Six hours? You'll understand why , I'm, I'm, I'm,
45:22 pointing at you. All right. who's taking acetaminophen? That's Tylenol.
45:28 often can you take? You take two acetaminophen? When can you take
45:32 next two acetaminophen? Four hours? important. Ok? If you're taking
45:40 leave, when's the next time you take on a leave? This is
45:45 fun 1, 12 hours, And then there's some drugs where it's
45:52 you can only take them once a . All right. The reason for
45:57 is going to be something that we're to look at in just a moment
45:59 the plasma clear. It's the rate which I can get rid of a
46:03 from my body. Now, the if we didn't have a process of
46:09 , the way that we'd get rid the substance that would be filtered and
46:12 presume there's no reabsorption, then we'd to wait for the blood to keep
46:17 through our body and it would just a little bit at a time until
46:20 eventually got away. Right. for example, using those three
46:25 which are all pain medications, Aleve, Ibuprofen, Mefin. I
46:31 even know what the name for Aleve . I usually have some pre farm
46:35 . Oh, yeah, the name blah, blah, blah,
46:36 And I'm like, ok, I never remember the way these things
46:42 . The reason that you can take you have these different times is because
46:47 rate at which your body gets rid them is different. And it's because
46:51 the secretion method here, right? these aren't just being filtered. They
46:55 these carriers that are looking for the and they are capable of binding up
47:00 metabolite and then picking them up from blood and moving them in. So
47:04 rate at which you're removing them is , much faster. And there's all
47:09 of these. And that's what this down here below is just showing some
47:12 the ones that we've identified. So are unique carriers for each of these
47:16 ions because the metabolites are ionic in nature, they either positively or negatively
47:21 . And so they're easily recognizable. so the carrier grabs them and move
47:25 , moves them across the membrane, ? So without these, the rate
47:30 removal would take longer. So let's of things that are bad for our
47:35 , right? Because the metabolites. of drugs is not, not that
47:39 of a deal. But let's say put a toxin in your body,
47:42 enough to kill you, but enough , you know, kind of make
47:45 ill, right? And if you had a filtration mechanism, then your
47:50 would be exposed to that for as as it took for it to filter
47:54 . And that means it would have circulate. So let's just say each
47:57 it passes by 50% of it right? So that means if you
48:03 off with 100%, the first time blood filters, through you lose half
48:07 the next time, however long it about five minutes, then you'd lose
48:11 half and then another half and then half. And you can imagine over
48:15 , it would take many, many before you finally got rid of it
48:19 a secretion system like this. What can do is say, all
48:22 maybe I'm only losing half during but maybe through the secretion method secretion
48:28 , I'm losing the other 50%. it only takes one route for all
48:33 the material to be removed from your . This is how we get rid
48:38 metabolites from like hormones, right? your body doesn't want those signaling molecules
48:44 around forever because they can turn on in inappropriate ways. So your body
48:50 in there like I don't want to rid of this as fast as I
48:53 . So this is the way we increase the rate of, of of
48:58 of materials that the body doesn't want through things like this, through the
49:05 . And again, that's, that's extent of it because like I
49:08 there are so many different types of involved here, separate types of
49:14 But the key thing here is materials that we put in our
49:18 the metabolites, metabolic waste that our is breaking down different molecules and even
49:25 hormones. You guys know what E T is good on you. I'm
49:36 . And the people who do are there going, I'm not gonna say
49:38 word E P T is a brand for the early pregnancy test. E
49:46 T. That's its name, You pee on the stick, you
49:50 out if you're pregnant and they you can find out within four days
49:56 , of, of uh basically uh . How do, how,
50:02 how, how does this work? are you measuring a hormone in the
50:08 ? Right. And really what it is not necessarily the hormone, the
50:11 has to be broken down. And what they're looking for is the
50:15 And how is that metabolite? Easily ? Well, because of the rate
50:18 secretion because of stuff like that. just an example. Anyone here ever
50:24 to take a drug test? Isn't that fun? Right. Get
50:28 job pee in the cup. Um, you know, before a
50:34 test you are never, ever, , ever, ever to go have
50:37 seed bagels or poppy seed muffins. you know why? Where do poppies
50:44 from or where do poppy seeds come ? Poppies? Where does heroin come
50:49 ? Poppies? And the metabolites appear same on the drug tests?
50:55 don't eat the poppy seeds before the test or you'll have to take it
51:01 over again. So if you're trying mask something, well, I'm not
51:05 say anything but again, same It's these types of mechanisms. All
51:14 . Are we good so far we with any questions about how we move
51:21 ? No, because I said at very beginning, wherever sodium goes water
51:28 , I could have let you guys . See, I told you,
51:30 said you could leave. I want talk now about the one thing that
51:37 I was in your seat where I it the first time and then put
51:41 fingers in my ears and said, la la, this is too
51:45 I'm not gonna learn this. And year that I took an anatomy course
51:49 physiology course, I did the same . And then once I had to
51:54 , I realized how easy it So wanna deal with urine concentration and
52:00 osmotic gradient. All right. Now all aware and I've, we've talked
52:04 this, that urine has varying concentrations upon your state of hydration,
52:10 So the more water you drink the , your pee is, the less
52:14 you drink and you become dehydrated, more concentrated it becomes, we're all
52:17 with that concept, right? So order for that to happen, that
52:22 we have to move water into the or leave it in the filtrate.
52:26 right. That's, that's the principle we're dealing with. And so the
52:29 is how does that happen? All . So the first thing I have
52:32 here on the slide is to point what our bla bla our blood osmolarity
52:37 relative to the interstitial fluid relative to cortex of the kidney. And I've
52:42 told you that we say that the of isotonic, the state of,
52:48 , of, of Materials in that is around 300 million osmoles. So
52:54 you match 300 million osmos, you're , which means that there is no
52:59 gradient which water doesn't move. It's happy wherever it is. So the
53:04 in your brain, the fluid in blood, the fluid everywhere in your
53:08 , that's the same osmolarity. So doesn't move into a particular direction because
53:14 osmotic considerations. But we've been talking osmotic considerations for quite some time
53:21 right? And the reason is because have channels and we have pumps that
53:25 moving salt. And so water moves response to energy usage because a salt
53:32 moving, but that's expensive, Energy wise, it's very expensive.
53:38 we want to create a system that use more energy than we're already
53:43 OK. That's the idea here. , if a fluid is hypotonic,
53:49 that's saying is that you have uh solute than normal. And so that
53:55 you have more water. So water gonna move away from that area.
53:57 if you're something as hypotonic, then extra solute. So water is gonna
54:02 towards that area, right? So you see those terms, it's easy
54:07 get confused. So just think hyper is more, is less and
54:11 And then tonic refers to solute. right. So that allows you to
54:15 , OK, if I have less , that means I have more
54:18 If I have more solute, that I have less water. All
54:22 Now, in order for us to water to move one way or the
54:27 , then we need to have that in osmolarity, we need to have
54:30 hypertonic or a hypertonic state. We want isotonic, we want to have
54:35 difference so that the water moves to it needs to go. All
54:39 So this is what that osmotic gradient I referred to has. And this
54:43 kind of shows that here out in cortex, you can see the 300
54:46 can see the value is going down 1203 100 down to 1200 all the
54:50 around. All right. And so osmotic gradient is what allows us to
54:55 water because the area around the tubule specifically the collecting tubule and the area
55:04 the loop of Henley has a different concentration. And so whenever I have
55:09 different solute concentration, wherever there is water follows. OK. So that's
55:15 we're looking at. All right. it's this, that allows us to
55:21 the concentration of our urine. how do we go about doing
55:26 Well, it's because first off, nephrotic loop is a countercurrent multiplier.
55:31 you can see that here in this here over here would be where Bowman's
55:35 is. So here I go, go down and then I go back
55:38 , that's countercurrent one direction, then other direction. And you can see
55:43 , I'm going to go back down more time. So countercurrent first to
55:48 flow of the fluid inside the it's going down and then it's coming
55:51 up again. That's the descending and ascending loop, the multiplier refers to
55:57 feedback mechanism that's going to allow us concentrate out the fluid first and then
56:05 the concentration second. So what we're do is we're gonna move salt and
56:10 gonna move water so that the filtrate its osmolarity as it passes through.
56:16 , this was happening as a result not the loop of Hindley through the
56:20 nephrons, but through the jua medullary , the ones that go down deep
56:24 come back up. So this is all this is actually taking place.
56:29 so what he said is that the of Henley is responsible for creating
56:32 this osmolarity difference, right, this gradient. And so how it works
56:38 a, in a very basic nutshell I'm gonna first focus over here.
56:43 right. So along the lengths of a sending loop is you have a
56:49 bunch of sodium pumps and the sodium are sitting there taking sodium from the
56:53 and pumping it out into the And so wherever sodium goes water
57:03 But on the ascending side, we not have aquaporin. So water can't
57:08 on that side. But on the loop, we have aquaporin. Now
57:15 things are right next to each other so, right, so if I'm
57:19 salt on this side, then water gonna be leaving on this side.
57:24 right, they're that close together even the picture doesn't look like that.
57:28 salt is leaving, making the filtrate and less concentrated on this side.
57:35 water is leaving, making the filtrate and more concentrated. And as the
57:40 leaves and comes out here, the environment becomes more and more concentrated and
57:47 the water leaving out helps dilute it some. And so what we end
57:51 with is in the deepest parts, is where we're going to have the
57:55 concentrations and in the shallowest parts nearest surface, that's where we're going to
58:00 the least concentrated. Now, this a really, really difficult concept and
58:08 really hard to see in a static like this. And so I think
58:12 have a video that's posted like after , if you want to see the
58:17 , you can kind of watch the to see what's going on. All
58:20 , but I'm not so interested in understanding every single solitary step along the
58:25 here. I just want you to what we're trying to do is we're
58:29 a mechanism to move salt to cause to move. That creates this environment
58:34 we're going to take advantage of. right, it's the environment that's
58:40 And then as the fluid is passing , it goes down, it starts
58:44 at about the same os malaria as body 300 it gets really, really
58:48 around 1200. But then as it back up, it becomes really,
58:52 dilute about 100 million osmoles. So urine that you're making, you
58:58 or the filtrate as it as it's through becomes more and more watery as
59:02 goes through. So your natural state to get rid of excess water.
59:09 . So your filtrate is extra watery to start off with. And if
59:13 else happened, then that filtrate would on through and out, it would
59:17 as extra watery urine. OK. you're not always over hydrated,
59:26 We need to make adjustments and look what the collecting duct does. It
59:32 through that same osmotic gradient that you created. So that's how it's
59:37 That's what the osmotic gradient does. that's what this slide is basically talking
59:42 . It's allowing you to create this . So that when the fluid passes
59:48 on its way out through the collecting , what I can do is depending
59:52 my need. If I'm, if dehydrated, I start producing vasopressin.
59:58 the vasopressin we said, introduces aqua into the collecting duct. And if
60:03 put aqua porns in the collecting there's extra salt out here. And
60:07 what's going to happen is the water the filtrate and now I'm making
60:11 very concentrated urine and it was I didn't expend any extra energy to
60:19 that happen. OK? If I'm dehydrated, vain, vain isn't
60:26 So the urine that I make is because I've made a very, very
60:32 filtrate. Now, we talked about vas erecta. Those are those long
60:41 layers that go alongside the loop of . Why do I care about the
60:46 erecta? Great. It's just one thing for me to memorize. All
60:50 . Well, every time water what does it do to the osmotic
60:55 ? Right? If water is leaving And water is passing out here and
61:03 is passing out there. What I'm is I'm making micro adjustments to that
61:09 . And so as we introduce more more water, I'm actually destroying the
61:15 gradient that I created. But a which is carrying blood that starts off
61:22 300 million osmos passes through there. so it lets water out and salt
61:27 in and it redistributes the water and salt. And so when you go
61:32 into a deeper concentrations, water but when you go back up
61:37 salt leaves and picks up water. that's where the redistribution comes along.
61:43 so while I'm making the gradient, also destroying it. But because the
61:48 is there, I pick up the that are destroying things and I redistribute
61:52 back to where they need to And so the osmotic gradient is
61:58 So we have a system that works a passive way to ensure that this
62:04 so that you can pee extra water expending any extra energy. That's the
62:11 purpose of this. Now, this is hard to see,
62:18 If I show you that picture I'll start there looking at that
62:23 Can you figure out what that Yeah, I mean, I don't
62:28 . No, I'm I'm with So if you want to understand how
62:33 doing it, watch the video that gonna post on blackboard. If you're
62:39 interested in knowing how like what are the steps. But you really,
62:43 key thing here is, oh I creating a vari a variable concentration on
62:51 outside. And I'm using that to water because you've already learned the
62:58 And so if I'm hydrated, I to get rid of water. So
63:03 not using the surrounding environment. It's there. But if I'm dehydrated,
63:10 can put in aqua pons and it draw water out of the, out
63:14 the filtrate so I can make something concentrated that a little bit easier.
63:26 . Are there questions? Like no , I'm not gonna ask a question
63:31 something like that. Fast question makes feel dumb. You wanna get
63:40 don't you? I mean more slides got Like 5, 3-5. I
63:47 we're almost done. Oh, there a question. Thank you. Get
63:56 of some excess vitamins. Mhm But some other vitamins I was like,
64:03 didn't quite to actually vitamin C gets too. It's just that much,
64:12 higher concentrations. So the question is , why can I uh have certain
64:18 and I can just kind of pee the stuff, right? The the
64:21 is it has to do with the sort of thing. We're gonna
64:24 really kind of, that's kind of the next thing is, is is
64:28 , plasma clearance. How fast do get rid of stuff? So every
64:32 in your body has a a specific it wants to maintain selenium. Do
64:37 ever think about your selenium? Do you ever think about your
64:41 No. Anyone anyone here ever bother think about how much selenium your body
64:45 . How about, how about the of zinc your body needs? That's
64:48 mineral, right? Ladies usually think iron for the most part guys tend
64:54 hold their iron a little bit right? But I mean, there's
64:58 sorts of calcium, you know, in your body has a specific concentration
65:03 can maintain and it will get rid the excess. But like thing like
65:08 vitamin C, you, you don't bother thinking about what that concentration
65:11 You start getting the toxic levels around mg. So if you like if
65:18 like me, you know, the C pills back in the day,
65:22 are they? They're basically sweet they're orange flavored sweet tarts. You
65:25 pop them. I'm the only one ever did that. It's like 600
65:33 don't do, don't do more than . All right, because that's when
65:36 body can't get rid of. And what we're talking about, its ability
65:39 get rid of it. It's like reached plasma thresholds and that's the
65:44 So your body does still get rid it. It just does so more
65:48 it wants to hold on iron specifically there's a lot of reasons to have
65:53 iron in. But your threshold, much iron you could have? It's
65:57 , oh, well, there's too and so it will start shedding
65:59 It's not, it's just not necessarily the urine primarily through feces.
66:07 I know we don't want to talk poop right now. But what's the
66:10 color of poop brown? And that's Billy Reuben, remember? So,
66:15 , it's from the hem and the . What was the other one that
66:20 asked about? It was another, vitamin, you said vitamin C,
66:24 E, vitamin K is another We don't actually consume a lot of
66:28 K. Um Here's a fun I mean, you guys, you
66:31 watch Big Bang, right? Did ever watch Big Bang Theory?
66:36 I mean, Jim Jim Parsons is U H alum. That's Sheldon,
66:42 ? There's a scene where he and penny go shopping and they're at
66:46 grocery store and she's picking out vitamins she's like picking out. He
66:51 oh, you don't want to buy . That's basically you're just um you're
66:55 just gonna pee it right out, ? And she see, she
66:59 well, maybe that's what I wanna . And then he says because he
67:02 all the chemical property, well, , maybe, then what you want
67:05 manganese because the amount of manganese in body is so low. It's kind
67:08 like selenium, you need it, it's very, very small.
67:20 So aqua porns, generally speaking. in an open state. But in
67:24 we're talking about the uh the cells the collecting ducts. So these are
67:29 principal cells, aqua porns are actually away. So there's vesicles that are
67:36 to the uh cell membrane and then away from the cell membrane. And
67:41 basically are are accumulations of the So what aldosterone does or assumably what
67:48 supress does is it's a signal that two things. The first thing it
67:52 , it says, hey, uh vesicles where you have all the aquaporin
67:56 to go ahead and move them to surface. And so that way you
67:59 the aquaporin so that they can be . But the other thing that it
68:02 , it tells the cell to make aquaporin. But notice, I don't
68:05 to wait for them to be They're already there. I just have
68:08 shift them to a place where they actually be functional. So it's kind
68:13 cool. Yeah. OK. Abs see that one, that one.
68:24 . Which right. So what this the question she's asking is, I've
68:34 this really weird statement down here. concentration increases from 1200 mil osmos to
68:39 . What this is referring to is concentration of the filtrate itself. All
68:45 . And so if you think about filtrate, just follow the arrows
68:48 what's going on is I'm starting the filtrate looks like rest of the
68:51 at 300 mil osmoles. But because the pumping that's going on over here
68:56 the fluid goes down, water So I start off at 300.
69:00 the inside of that tube becomes more more concentrated. So when I get
69:04 here, I'm matching the surrounding environment 1200 Miasmas right now, that's a
69:09 of the salt pump out over there that the water will fall over
69:14 All right. But as the so now I'm down here, so
69:17 1200 million osmoles, as that fluid back up, remember, it's going
69:23 and salt is being pumped away from and it's a constant rate at which
69:26 being pumped. So as you're traveling up, that filtrate inside, Because
69:32 salt is leaving goes from 1200 and passes, passes past it and it
69:37 beyond 300, it goes to And so by the time you get
69:43 out here into the cortex in the convoluted tubule, you're now more watery
69:49 you started off with. All Now, that concept, that idea
69:54 , is a little bit kind of , wow, that's a lot.
69:57 a lot going on there. But I've done here is using a mechanism
70:01 I can take advantage of. I'm two things first, I'm creating an
70:05 that I'm gonna take advantage of. . That's number one. And then
70:08 two is I've made urine or really , that's water more watery than it
70:15 when I started. So I went 300 to 100. But in doing
70:20 , I had to pass through AAA of concentration before I became more
70:27 So that's what's going on. And what that statement refers to anyone
70:34 10 minutes to go through the last slides. G F R G F
70:42 is the GME filtration rate. We've talked about the rate at which the
70:46 is formed per unit time. It's your doctor uses to determine your kidney
70:52 when you go to the doctor and take your blood and they go make
70:55 pee in the cup. What they is they're looking for two different elements
70:59 and they're basically using a formula that has been well established to kind
71:03 determine whether or not your kidneys are correctly. All right. Now,
71:09 there are real issues, what they'll is they'll inject you with this uh
71:13 sugar. It's called inulin, not . It's inulin. And what inulin
71:17 , is a, it's a plant and it can't be broken down and
71:20 can be filtered and so it can't reabsorbed, it can't be secreted.
71:24 they can measure it and they just look at what is its concentration in
71:28 urine, what's it, concentration of plasma and what's the volume of urine
71:32 you've collected? And so they can that to calculate it out. What
71:35 real, your true G F R is as opposed to the calculated one
71:40 they give you just by taking your and taking um your urine. Because
71:44 that no one's ever given you any when you've gone to the doctor.
71:47 right. So if you have a G F R, that's an indicator
71:54 decreased kidney function. And so the that we normally evaluate how kidney is
72:01 is through this G F R. really what we're asking is is what
72:05 the renal plasma clearance rate? remember we just talked a moment ago
72:10 three different drugs, right? And talked about the the rate at which
72:15 things are removed from the body. in six hours, you can take
72:21 because the rate at which you're removing from your body takes about six hours
72:26 that you're, you're uh clearing Is there anyone who takes them?
72:30 don't wanna know the medication but anyone take a medication like daily, just
72:34 , right? So just so you , you're not going from uh you
72:38 , taking your drug and you're going and then it's leaching down to
72:42 So you take, take your drug , right? What's happening is is
72:46 you take it on a regular the rate of clearance allows you to
72:50 . So you take it up 100% it doesn't go down to zero,
72:53 goes down to let's say 25%. the next time you take it,
72:56 now at 100 and 25 now you down to 50. And what ends
73:00 happening is you then have over a of a couple of days reach a
73:04 where you now are saturated in that and the body is not able to
73:10 it. That's plasma clearance. plasma clearance is a weird way of
73:16 things. I'm not gonna pretend that makes any sense to normal humans.
73:21 . What it is is the volume plasma cleared of a particular substance per
73:27 . So what we're doing is we're the volume, not the amount that's
73:31 the in the volume. So let's you have 100 mg of something in
73:34 blood. They're not asking you, long did it take you to remove
73:36 100 mg? They're asking you how , how much volume is passed to
73:44 that substance which is backwards if you me, but no one asks me
73:49 it's not my math. OK. substance has a different plasma clearance
73:55 ibuprofen every six hours, acetaminophen every hours, Aleve every 12 hours.
74:03 what this does is it demonstrates how we can remove or how, what
74:08 body's ability is to remove that substance itself. Now, the last little
74:13 here that's, that's key about this when you look at a substance,
74:16 can kind of look at it and these questions like, all right,
74:20 I'm trying to look at a is it moving, is it or
74:24 faster or slower than the G F ? So for example, if a
74:30 is not going to be reabsorbed and it's not going to be secreted,
74:35 the rate at which I'm removing it the rate at which I can filter
74:38 if that makes sense. So that's that has a plasma clearance rate equal
74:43 the G F R. So inulin one of these types of substances.
74:48 right, that's why they give it you because they know it's neither reabsorbed
74:52 is it secreted. So the rate which it's passing through this is
74:55 this is your G F R. then we have substances that are
75:00 These are the things that your body , right? And so what you're
75:04 for is something if, when you're at a substance, you're asking the
75:08 , is it being reabsorbed completely or it staying in the filtrate? So
75:13 have things that are complete like the body desperately wants to keep the
75:18 . So its plasma clearance is right? You do not ever get
75:24 of it except under pathological conditions, urea has a partial plasma clearance,
75:33 ? It's partially reabsorbed. So there a plasma clearance, but it's less
75:37 the G F R. So if F R is here, urea would
75:40 down here zero. Would we be over here? And then we have
75:45 we want to secrete. So these the medications, these are protons,
75:48 example, they're not going to be . Instead, they're both filtered and
75:53 . So when you take your your body is not going well,
75:56 want to keep some of that. just saying I want to get rid
75:59 this. And so its plasma clearance going to be greater than the G
76:04 R. All right. And so you look at a drug and they're
76:10 you take it this often, don't it more than this. It's because
76:16 dealing with, if you take it than this, you can't clear it
76:19 enough. So you start building up levels of that material. Ok.
76:28 little bit, I guarantee you none this will be on the test because
76:35 , so you can start packing yourself , right? Basically, there are
76:38 of urine, it's sterile, it's water plus stuff in it. You
76:45 about 1 - two L per Think about how often you go to
76:51 bathroom, right? I mean, you can count it up,
76:55 You wake up in the morning probably morning right after lunch, mid
77:00 right after dinner, probably one more before you go to bed, maybe
77:05 before you go to bed. And pee out anywhere between 254 100 mils
77:10 the math there. Six times 400 six times 22 50. You'll find
77:18 in those numbers. If you drink water, what's gonna happen, you're
77:23 pee more. There you go. that's not hard. P range is
77:27 4.5 and eight. You're averaging around . Remember we said diet affects this
77:31 little bit here. It's heavier than . Does that make sense that it's
77:35 than water? So specific gravity is greater than water. So when you
77:40 in the toilet notice that the urine filters downward, right? It's really
77:46 solutes that are in there. Color from clear to some really strange and
77:50 things depending upon the concentration of the in. That's why you get those
77:55 colors. If you're interested to see colors, what they mean. Some
78:01 these are the fun ones like red , beets and blueberries, you can
78:06 red when I was in high I went to a boarding school and
78:09 of the things we did was we a hold of methylene blue. We
78:13 it in the Kool Aid. One drank like, I don't know,
78:17 10 glasses of Kool Aid and then peed blue food die. So
78:25 he freaked out. It was Um Turbidity is clear but it can
78:31 cloudy. Um uh because of certain and lastly a smell there, the
78:38 smell is called rino. Like I'm , you're annoyed. So you're
78:44 That's the smell of fresh urine. you have weird smells, that can
78:49 indicate pathologies. Asparagus is not a . That's just your inability to break
78:55 a spare gene. So some of recognize that when we eat asparagus,
79:00 smell the urine smells terrible. Some you are like, I don't know
79:03 you're talking about. That means you break down a spare jean. The
79:07 of us can't and you'll know. anyway, um I want you guys
79:12 have a fun spring break. Remember only assignment you have is to read
79:18 remember you can read starting on Sunday , after spring break. So you
79:23 , go have fun, stay Don't do stupid
-
+