Endocrine functions of the Kidney ILA

Question 1

4 main hormones the kidney produces

Answer 1

erythropoietin
renin
active vitamin D
Prostaglandins

Question 2

6 hormones the kidney responds to

Answer 2

Aldosterone
ANP
ADH
PTH
Vitamin D
FGF-23

Question 3

stimulus for kidney to make erythropoietin (EPO)

Answer 3

low oxygen levels

Question 4

what does an increase in erythropoietin (EPO) cause

Answer 4

increase in plasma RBC’s

Question 5

may result from renal cell carcinoma depending on whether EPO is secreted by tumor or not

Answer 5

EPO excess or deficiency

Question 6

results from chronic kidney disease (EPO)

Answer 6

EPO deficiency

Question 7

EPO deficiency leads to

Answer 7

anemia

Question 8

what produces renin

Answer 8

JG cells

Question 9

what stimulates JG cells to produce renin (3 things)

Answer 9

1. decreased perfusion pressure sensed by baroreceptors (afferent arteriole)
2. increased SNS stimulation(B1)
3. decreased Na levels (sensed by macula densa cells)

Question 10

converts Angiotensinogen to Angiotensin I

Answer 10

renin

Question 11

what converts Ang I to Ang II

Answer 11

ACE (from lungs and kidneys)

Question 12

1alpha-hydroxylase

Answer 12

origin of active vitamin D in kidney

Question 13

what stimulates kidney to make vitamin D

Answer 13

PTH (responding to low plasma Ca2+)
low plasma phosphate

Question 14

what increases Ca2+ and phosphate absorption from the gut and kidney

Answer 14

vitamin D

Question 15

low levels of active vitamin D result from (2 things)

Answer 15

renal insufficiency
hypoparathyroidism

Question 16

hereditary vitamin D resistant rickets causes what

Answer 16

excess of active vitamin D

Question 17

dilate afferent arterioles to increase RBF and GFR

Answer 17

prostaglandins (PGE2 and PGI2)

Question 18

blocks prostaglandins and causes afferent arteriole vasoconstriction

Answer 18

NSAIDs

Question 19

4 main functions of RAAS

Answer 19

1. vasoconstriction
2. tubular reabsorption of Na+ and H2O
3. aldosterone secretion
4. ADH secretion

Question 20

Ang II binds and activates what receptors

Answer 20

AT1R (Gq)

Question 21

constricts vascular smooth muscles in periphery and kidney (decreases GFR)

Answer 21

Ang II

Question 22

increases aldosterone secretion and ADH secretion

Answer 22

Ang II

Question 23

activates receptors in the brain to increase thirst

Answer 23

Ang II

Question 24

made in zona glomerulosa of adrenal cortex

Answer 24

aldosterone

Question 25

Ang II and increased plasma K+ stimulate this production

Answer 25

Aldosterone

Question 26

____ exerts its actions through mineralcorticoid receptors in the DCT principal cells

Answer 26

aldosterone

Question 27

increases synthesis and membrane expression of ENaC (Na+) and ROMK (K+) channels at luminal membrane

Answer 27

aldosterone

Question 28

increases synthesis and membrane expression of Na+/K+ ATPase at basolateral membrane

Answer 28

Aldosterone

Question 29

promotes Na+ retention and K+ elimination by the kidney

Answer 29

aldosterone

Question 30

excess aldosterone causes what

Answer 30

HTN, hypokalemia, alkalosis

Question 31

____ regulates H+ secretion by kidney and can cause alkalosis

Answer 31

aldosterone

Question 32

how does the mineralcorticoid receptor ever see aldosterone w/ excess cortisol?

Answer 32

DCT express HSD2 that inactivates cortisol to cortisone

Question 33

what can cause cortisol level elevation and overwhelming of HSD2 receptors

Answer 33

Cushing's disease

Question 34

what stimulates ANP

Answer 34

stretch of atria (volume overload)

Question 35

causes vasodilation of renal afferent arterioles and vasoconstriction of efferent arterioles

Answer 35

ANP

Question 36

net effect of this is to increase GFR

Answer 36

ANP

Question 37

mediates escape from effects of aldosterone during excess aldosterone

Answer 37

ANP

Question 38

promotes natriuresis (loss of Na+)

Answer 38

ANP

Question 39

made in magnocellular neurons of supraoptic and paraventricular nuclei of hypothalamus

Answer 39

ADH (vasopressin)

Question 40

secreted from posterior pituitary

Answer 40

ADH

Question 41

what stimulates ADH to be released from posterior pituitary

Answer 41

increase in plasma osmolality hypovolemia (decrease in blood volume) Ang II

Question 42

receptor ADH activates

Answer 42

V2 (Gs); cAMP/PKA

Question 43

these are inserted in luminal membrane of collecting duct and allow for water reabsorption

Answer 43

aquaporin 2 channels

Question 44

what stimulates PTH release

Answer 44

low levels of Ca2+ in circulation high phosphate levels

Question 45

PTH action on DCT

Answer 45

Ca2+ reabsorption

Question 46

PTH action on PCT

Answer 46

phosphate excretion

Question 47

excess PTH leads to

Answer 47

hypercalcemia; hypophosphatemia

Question 48

deficiency of PTH leads to

Answer 48

hypocalcemia; hyperphosphatemia

Question 49

leads to increased active vitamin D and bone resorption

Answer 49

PTH

Question 50

made in bone osteocytes

Answer 50

FGF-23

Question 51

high levels of phosphate and elevated active vitamin D stimulate this production

Answer 51

FGF-23

Question 52

at PCT, FGF-23 does what to phosphate

Answer 52

increases phosphate excretion

Question 53

reduces vitamin D activation

Answer 53

FGF-23

Question 54

excess FGF-23 leads to

Answer 54

hypophosphatemia

Question 55

deficiency of FGF-23 leads to

Answer 55

hyperphosphatemia