KEEF REVIEW Flashcards
Four things that shift K+ INTO cells.
- Insulin
- B-agonists
- Aldosterone
- Alkalosis
Three things that shift K+ OUT of cells.
- Hyperosmolarity
- Exercise
- Cell lysis
What is the typical relationship of K+ and H+ ?
Reciprocal relationship
Four things that increase K+ secretion.
- Aldosterone
- Hyperkalemia
- Furosemide
- Thiazide diuretics
Where is glucose reabsorbed?
In the proximal tubule
Where is inulin concentration the greatest?
In the collecting duct
Where is PAH secreted?
In the proximal tubule
Where is creatinine secreted?
In the proximal tubule
Approximately what percentage of urea is excreted?
40%
What TWO things is excretion of urea dependent on?
- presence of ADH
2. flow (greater flow = greater clearance)
Approximately what percentage of glucose is excreted?
0%
Approximately what percentage of inulin is excreted?
100%
Approximately what percentage of PAH is excreted?
500%
Approximately what percentage of creatinine is excreted?
120%
Where is the primary site of ANP action?
Proximal tubule and collecting duct!
Why does plasma oncotic pressure go up along the glomerular capillary?
Water reabsorption!
Why is glomerular hydrostatic pressure so high?
The efferent arteriole creates resistance
What conc. of PAH would you need to use to get an accurate estimate of RPF?
A concentration lower than Tm!
Equation for reabsorption rate
RR = filtered load - excretion rate
Equation for secretion rate
ER = excretion rate - filtered load
Equation for free water clearance
V = Cosm + CH20
What creates the interstitial gradient in the nephron?
The Loop of Henle
What percentage of water is reabsorbed in the proximal tubule?
67%
How does flow out of the vasa recta compare to flow in?
Twice as much, because salt is reabsorbed, which leads to water flowing in
How does flow into glomerular capillary compare to flow exiting?
20% less
What arteriole does AngII primarily regulate?
Efferent!! By doing so, it allows for an increased GFR
How does ADH increase water absorption?
It activates a Gs receptor, which increases CAMP concentration, and draws aquaporins to the apical membrane.
During diuresis, at what point along the nephron is the urine osmolarity the lowest?
At the collecting duct
With hemorrhage, would ADH increase or decrease?
Increase!
