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Flashcards in adrenal physio Deck (38)
1

cortisol is primarily produced in what layer of the adrenal cortex?

zona fasciculata

2

androgens are primarily produced in what layer of the adrenal cortex?

zona reticularis

3

epi and NE are produced in the adrenal______

medulla

4

what enzyme converts testosterone into DHT?

5-alpha reductase

5

what is the rate limiting step of cortisol biosynthesis?

conversion of cholesterol into pregnenolone

6

female adrenal derived testosterone is important in maintaining?

normal pubic and axillary hair

7

in post-menopausal women, adrenal derived testosterone is a source of?

estradiol

8

ACTH binds to what sort of receptor?

melanocortin 2 receptor

9

chronic low levels of ACTH cause______

cortical atrophy

10

chronic elevated levels of ACTH cause______

cortical hypertrophy

11

how does stress increase plasma glu levels via cortisol (2)

1. incr gluconeogenesis
2. decr glu utilization

12

___appetite incr glucocorticoids

increased

13

effect of glucocorticoids on bone?

incr reabsorption of bone

14

besides aldosterone, which enzymes have slight mineralocorticoid activity? (2)

1. 11-deoxycorticosterone (DOC)
2. corticosterone

15

example of a synthetic mineralocorticoid?

fludrocortisone

16

used to tx primary adrenal insufficiency

fludrocortisone

17

main regulators of aldosterone synthesis (2)

1. ATII
2. blood potassium levels

18

ATII binding leads to incr in intracellular Ca-->incr expression of ____ and _____

StAR and P450scc

19

____blood potassium depolarize zona glomerulosa cells

elevated

20

aldosterone leads to ____Na excretion and ___K excretion

decr; incr

21

which enzyme converts cortisol from inactive to active form?

11beta-HSD1

22

which enzyme converts cortisol from active to inactive form?

11beta-HSD2

23

11beta-HSD2 is found where? (3)

1. kidney
2. colon
3. salivary glands

24

saturation of 11-beta HSD2 can occur during which disease?

hypercortisolism

25

genetic disease caused by inactivation of 11-beta HSD2

apparent mineralocorticoid excess (AME)

26

can cortisol bind MR?

yup

27

XY; ambiguous genitalia, undescended testes

17-alpha hydroxylase deficiency

28

XX, lack secondary sexual development

17-alpha hydroxylase deficiency

29

XX infants with male genitalia, salt wasting crisis, children with precocious puberty, incr in 17-OH progesterone

21 hydroxylase deficiency

30

virilization, incr DOC levels, no salt wasting

11 beta hydroxylase deficiency

31

when would you have a 50% reduction in cortisol and ACTH with a dexamethasone suppression test?

pit hypersecretion of ACTH

32

what is the rate limiting step of catecholamine biosynthesis?

tyrosine hydroxylase

33

what enzyme converts NE to Epi?

PNMT

34

what does COMT convert NE into?

normetanephrine

35

what converts normetanphrine and metaneprhine into VMA?

MAO

36

what does COMT convert epi into?

metanephrine

37

____has a greater effect on activation of alpha receptors

NE

38

____has a greater effect on activation of beta receptors

epi