Kidney Function 2

Question 1

which hormone controls water in kidney?

Answer 1

ADH/vasopressin

Question 2

Calcium almost entirely absorbed where?

Answer 2

proximal tubule

Question 3

what hormones control calcium in distal tubule? 2

Answer 3

parathyroid

vitamin D3

Question 4

where is phosphate reabsorbed?

Answer 4

80-90% proximal tubule

Question 5

Na+ absorbed where?

Answer 5

proximal tubule

Question 6

glucose is 100% absorbed where?

Answer 6

proximal tubule

Question 7

where are proteins and AAs reabsorbed?

Answer 7

proximal tubule

Question 8

how much creatinine is reabsorbed?

Answer 8

None!

Question 9

Urea comes from what? Loose gauge of what?

Answer 9

breakdown of proteins

gauge for renal function

Question 10

3 layers of osmolarity in kidney are?

Answer 10

outer
inner
pila/deep

Question 11

What’s so good about concentration increasing as you go deeper into kidney?

Answer 11

enables body to respond to diverse situations

Question 12

water reabsorbed?
70%
20%
7%
3%

Answer 12

70% in proximal tubule
20% thin ascending loop
7% distal tubule
3% collecting duct

Question 13

Na+ absorbed how and where?

Answer 13

active transport

proximal tubule

Question 14

Na+ reabsorbed, what else follows? where? how?

Answer 14

anions: Cl- and bicarb
transcellular/paracellular space
via electrochemical gradient

Question 15

‘tight’ junctions in proximal tubule are water tight?

Answer 15

Nope, pretty leaky to water, Na+,

Question 16

Na+ absorbed and anions, what else? how? why?

Answer 16

H20
via osmotic gradient
50/50 transcellular/paracellular

Question 17

H20 is absorbed in proximal tubules via osmotic gradient, what else is absorbed with it? 3 things

Answer 17

K+, Ca2+, urea because it’s dissolved in the H20 and diffuses

Question 18

___% of O2 consumed by kidneys?

Answer 18

80%

Question 19

electrochemical gradient in proximal tubule is how many mV?

Answer 19

-3mV

Question 20

in the late proximal tubule, why do you get Na+ leaking back into lumen?

Answer 20

Bicarb get absorbed preferentially over Cl- as anions try to follow Na+ initially
So build up of Cl-, and it sucks out the Na+ at end of proximal tubule

Question 21

at the end of distal proximal tubule there is a high concentration of what?

Answer 21

Na+ Cl-

Question 22

What is reabsorbed in the thin ascending limb? how?

Answer 22

Na+ via passive diffusion through paracellular tight junctions

Question 23

frusemide targets what? where?

Answer 23

Na+, K+ 2Cl- cotransporter in loop of henle

Question 24

danger of frusemide?

Answer 24

Kypokalemia

Question 25

water reabsorbed in thick ascending tubule?

Answer 25

Nope, tighter tight junctions

Question 26

What happens to Na+ in thick ascending limb?

Answer 26

lots gets reabsorbed

50/50 paracellular/active transport

Question 27

in Thick ascending limb what transporter is now in the baso-latreal border instead of Na/HCO3?

Answer 27

Cl/HCO3 which encourages Na+ to stay in and not leak back out

Question 28

What happens to Na+ in distal convoluted tubule?

Answer 28

almost all gets reabsorbed via transcellular route

Question 29

Where do thiazides work? why not as powerful as frusemide?

Answer 29

NaCl cotransporter block in distal convoluted tubule, not as powerful cause only affecting 5% of fluid

Question 30

What is ENAC? where is it?

Answer 30

epithelial sodium channel in collecting duct passive sodium in

Question 31

what happens to K+ in CD?

Answer 31

passive out into lumen