# 05 Nephron Physiology

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/ignore/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/cFJpFhz.jpg)

* high to low concentration: no energy needed

![](https://f001.backblazeb2.com/file/wikiFiles/ouyt2Bq.jpg)

* paracellular: between cells

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/nephron,%20osmolarity%20definition.%20How%20does%20water%20move%20between%20osm)..

![](https://f001.backblazeb2.com/file/wikiFiles/YUh60yQ.jpg)

* osm: how much solute dissolved in water 
* low osm: high concentration of water, vice versa
* water move from high concentration to low concentration

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/segments%20of%20nephron/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/AHoiXu8.jpg)

## PCT

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/PCT%20function,%20major%20diseases,%20most%20common%20diseases/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/iAgrKGE.jpg)

* work horse of nephron
* most absorption

![](https://f001.backblazeb2.com/file/wikiFiles/rc11G54.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/0u2Gh8s.jpg)

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/PCT%20ions%20and%20absorption,%20water/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/J2uiIxN.jpg)

* use concentration of Na to drag glucose in

![](https://f001.backblazeb2.com/file/wikiFiles/fFUK8jq.jpg)

* K pump into cell, diffuse out and drag Cl with it, lower Cl concentration in cell
* Cl can then be pulled into cell in exchange for anion

![](https://f001.backblazeb2.com/file/wikiFiles/0MFhs1I.jpg)

* water reabsorbed paracellularly via high Na/Cl concentration in blood

![](https://f001.backblazeb2.com/file/wikiFiles/EBYNxPQ.jpg)

### Glucose Clearance

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/glucose%20absorbed%20where%20in%20kidney,%20how,%20when%20appear%20in%20urine.%20When%20are%20transporters%20saturated.%20Physiologic%20glucosuria,%20why)..

![](https://f001.backblazeb2.com/file/wikiFiles/W9tBFoW.jpg)

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/aa%20absorbed%20where%20in%20kidney.%20Disease%20pathogenesis,%20symptoms)..

![](https://f001.backblazeb2.com/file/wikiFiles/lzNCIko.jpg)

* pellagra: B3 deficiency (niacin). Tryp converted to niacin

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/bicarb%20absorbed%20where%20in%20kidney,%20how/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/0HzzlsQ.jpg)

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/type%202%20RTA%20is,%20result/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/16WZ2Ap.jpg)

### Fanconi

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/fanconi%20syndrome%20cause,%20symptoms,%20electrolyte%20changes,%20result/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/XM7ki3P.jpg)

* proximal tubule disfunctional
* phosphate leads to growth failure

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/fanconi%20syndrome%20inherited%20disease,%20acquired%20causes/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/mam8FrI.jpg)

## Descending Loop

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/descending%20loop%20major%20functions,%20water/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/uuDVMkP.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/EBYNxPQ.jpg)

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/descending%20loop%20osmolarity%20changes,%20how/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/P6BJobq.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/031va29.jpg)

* Cortex: water drawn out until lumen = 300
* medulla: continue drawn out

## Ascending Limb

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/ascending%20limb%20ion%20channels,%20water/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/SJ02ao5.jpg)

* K leak into lumen, cause + charge and push cation in
* NKCC: Na, K, Cl, Cl

![](https://f001.backblazeb2.com/file/wikiFiles/EBYNxPQ.jpg)

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/ascending%20loop%20osm%20changes,%20how/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/zXUCTZ0.jpg)

* NaCl pulled out, leave water in, very dilute urine
* impermeable to water

![](https://f001.backblazeb2.com/file/wikiFiles/EBYNxPQ.jpg)

## Distal

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/DCT%20ion%20channels,%20water/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/HOg0WC5.jpg)

* PTH and thiazide diuretics increase Ca absorption 

![](https://f001.backblazeb2.com/file/wikiFiles/EBYNxPQ.jpg)

## CD

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/CD%20cells%20and%20ion%20channels,%20water/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/cU0Q63B.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/EBYNxPQ.jpg)

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/CD%20major%20function,%20depend%20on%20what%202%20hormones/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/zdbblK8.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/FoMEPxe.jpg)

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[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/Aldosterone%20is,%20made%20where,%20binds%20what,%20function,%20stimulated%20by%20what/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/n9xNB9K.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/KLHxLXD.jpg)

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* Ang II most important

### ADH

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/ADH%202%20receptors%20and%20functions,%20made%20where,%20stimulated%20by/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/d3HqCG4.jpg)

* vasopressin: vasoconstriction
* supraoptic/paraventricular

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/V2%20receptor,%20second%20messenger,%20result/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/crIesW7.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/OzM5QRI.jpg)

* AQP 3 and 4 always present: basolateral always permeable to water

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/water%20deprivation,%20ADH%20result,%20CD%20result/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/MOdKzEx.jpg)

* water deprived: concentrate urine by pulling it out

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/high%20water%20intake,%20ADH%20result,%20CD%20result/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/NT8XA9f.jpg)

* water not absorbed, NaCl absorption dilute urine

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/diuretics%20main%20MOA/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/qRMiE7n.jpg)

* high osmolarity in lumen at CD: less water leaving

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/ADH%20and%20urea/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/dGOevOJ.jpg)

* water leaving causes urea in lumen to be more concentrated: urea leaves via gradient
* ADH promotes absorption of urea

![](https://f001.backblazeb2.com/file/wikiFiles/VLWsCGr.jpg)

* urea pushed out in distal CD
* urea needed in descending loop to draw water out

## Misc

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/Na%20and%20water%20reabsorption%20along%20nephrons/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/SzGvWms.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/koFANEQ.jpg)

![](https://f001.backblazeb2.com/file/wikiFiles/EBYNxPQ.jpg)

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/concentration%20changes%20of%20NaCl,%20glucose,%20bicarb,%20inulin,%20Cr%20as%20they%20go%20down%20nephrons/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/fpZpCoq.jpg)

* middle: pull more solute out than water, result = more dilute
* bottom: pull water more than solute

[\_](https://github.com/thisispiggy/my-wiki/tree/601ff771dc2fac1318ae8b59435ac8485628fd81/01%20Step%201/Renal/tubule%20over%20plasma%20concentration%20changes%20in%20PCT/README.md)..

![](https://f001.backblazeb2.com/file/wikiFiles/tKIjKMd.jpg)

* inulin/Cr: not absorbed, concentration rises
* Cl/urea/Na/K: not really changed, concentration a little higher
* glucose/aa/bicarb: absorbed, concentration decreases
* PAH: secreted