Lecture 8 Final Flashcards
What is the plasma and solute osmolarity in the PCT?
300 mOsm
Do we have NaCl being reabsorbed in the Thin ascending loop?
Yes
How many % of solutes get reabsorbed at the thick ascending loop of henle?
25%
Right at the end of TAL and beginning of the DCT, the concentration level is?
100 mOsm
T/F:
ADH allows the renal system to reabsorb only H2O.
False, it also reabsorbs urea.
Creatinine concentration gets lower or higher throughout the tubule?
Higher d/t water reabsorption
What happens to the NKCl2 in the loop of henle?
They are reabsorbed causing a decrease in concentration
What is the PAH concentration in the tubule vs 1ml of plasma in the collecting tubule?
585
What is the creatinine concentration in the tubule vs 1ml of plasma in the collecting tubule?
120
What is the inulin concentration in the tubule vs 1ml of plasma in the collecting tubule?
125
What is the urea concentration in the tubule vs 1ml of plasma in the collecting tubule?
50-60
During diuresis, how much fluid in the interstitium vs in the plasma?
4/5 in the interstitium
1/5 in plasma
Based on the CV system, what is 1/5 of fluids that will be pulled from the plasma for urination during diuresis?
200 - 220ml (1/5)
T/F:
If pressures are too high, you can pull fluids from the ECF via diuretics?
True
Based on balance, if we eat a lot of salt, what does the kidneys do?
It lowers the angiotensin II to decrease Na+ reabsorption
What happens if you have abnormally high angiotensin II?
high BP
What does it mean if you have some type of angiotensin II blockade?
Low angiotensin II > low aldosterone > unable to retain salt/water > low BP
What happens if #1 of your kidneys are stenosed?
kidney 1
low pressures, low NaCl > inc. renin > inc. ang II > inc. MAP
kidney 2
Senses inc. MAP > dec. renin > but not enough to match the high renin in kidney 1 > HTN (but not as high that it could be)
Which meds work well for ang II problems?
ARBs
What is the build up of structures of the GCs?
Podocytes
What can happen to the GCs if exposed to pressures > 60 mmHg for too long?
damaged capillary beds
How does taste buds work?
It has Na and K channels. Na influx, K efflux, cell becomes excited. More Na+ > inc excitability (more taste).
*no Cl- channels
What are salt substitutes made of?
K+; makes food taste weird
How does the renal respond to high Na intake?
High Na+ > sensed by MD > dec. ang II > dec. aldosterone
High fluid volume > high Pcap > high GFR > high Na+ to MD > dec. ang II > dec. aldosterone > inc. excretion
Do African/africans have salt sensitive HTN?
No, only African Americans.
African Americans have low renin levels but responds to ACEi.
How does mannitol work?
It doesn’t get reabsorbed so it all gets excreted.
How does ARBs/Ace i work?
Blocks Ang II > less NA reabsorption
What does K sparing meds affect?
Aldosterone
What is normal creatinine clearance for 1mg/ml?
Filtered = 1mg/dl x 125ml/min = 1.25mg/min
(nml Cr secreted/min = 0.15mg/min)
Excretion rate = secreted + Filtered
1.40 = 0.15 + 1.25
What is the normal excretion rate compared to production rate?
It’s balanced (equals each other)
What would happen to our Cr. clearance if we lost 1 kidney?
normally we excrete 1.25mg/min
now it’s 0.625mg/min (cut in half).
Since we’re only removing half of what’s being produced, Cr levels rises to dbl concentration in order to remove the same amount produced.
T/F:
Production is not equal to excretion
False; If production (ex. Cr) is not equal to the excretion rate, the concentration will keep doubling until it’s equal.
Nephron Math???
What restrictions needed for kidney failure? Problems?
Restriction: Na, K, protein
Problems: Acidosis, hyperK, hyperNa, hypervolume, HTN
What happens if you add an isotonic solution?
Increased ECF
What happens if you add a hypotonic solution?
Osmolarity drops
increase ICF
Increased ECF
What happens if you add a hypertonic solution?
Osmolarity increase
Decreased ICF
Increased ECF
