V-Regulation of Kidney Function

Question 1

glomerulotubular balance

GTB

Answer 1

tubule response to change/fluctuation in filtration rate in the glom of the same nephron

Question 2

tubuloglomerular feedback

Answer 2

glomerular response to change/fluctuation in NaCl in the tubule of the same nephron

controls GFR by feeback on renal arteriolar resistance

Question 3

juxtaglomerular apparatus

Answer 3

senses changes in NaCl via macula densa cells in distal nephron and juxtaglomerular cells in wall of arterioles

Question 4

TGF mechansim

Answer 4

1. GFR increase
2. NaCl concentration in fluid at macula densa rises
3. more NaCl enters macula densa cells
4. vasoconstrict afferent arteriole
5. GFR return to normal

Question 5

renin-angiotensin pathway

Answer 5

1. stimulation of renin release from juxtaglomerular apparatus by dec perfusion pressure, beta-adrenergic stim, dec NaCl to macula densa
2. cleave angiotensin to ang-I
3. ACE cleave to ang-II

Question 6

effects of angiotensin II

Answer 6

1. stims aldosterone secretion
2. enhance NaCl re-abs
3. vasoconstrict renal arteriole so dec GFR

Question 7

effect of aldosterone

Answer 7

acts on collecting duct to inc NaCl absorption and K secretion

Question 8

atrial natriuretic peptide does

Answer 8

1. promotes NaCl and water excretion
2. directly inhibit NaCl reabsorption by collecting duct
3. inc GFR

Question 9

inc sympathetic activity

Answer 9

1. inc NaCl and water re-abs
2. vasoconstrict so dec GFR

Question 10

effect of PTH

Answer 10

1. stimulates Ca re-abs in hypocalemic state and v/v
2. inhibit phosphate re-abs
3. stim vit D activation to calcitriol

Question 11

effects of calcitriol

Answer 11

1. inc plasma Ca by stim absorption from intestinal tract
2. enhance Ca re-abs in kidneys

can be inhibited by FGF-23

Question 12

erythropoietin production

Answer 12

@ kidneys by interstitial fibroblasts

sense O2 so stim by hypoxia

Question 13

plasma Ca regulated by

Answer 13

PTH and calcitriol

Question 14

plasma phosphate regulated by

Answer 14

PTH, FGF-23, calcitriol