Exam 3 Lesson 19 Flashcards
(50 cards)
Pathway from cholesterol to aldosterone/mineralocorticoids
Cholesterol – pregnenolone – progesterone – deoxycorticosterone – corticosterone – 18-hydroxycorticosterone – aldosterone – mineralocorticoids
pathway from cholesterol to cortisol/glucocorticoids
Cholesterol – pregnenolone – 17-hydroxypregnenolone – 17-hydroxyprogesterone – 11-deoxycortisol – cortisol/glucorticoids
pathway from cholesterol to androstenedione/androgens
Cholesterol – pregnenolone - 17-hydroxypregnenolone – Dehydroepiandrosterone – androstenedione / androgens
pathway from progesterone to cortisol/glucorticoids
Progesterone – 17-hydroxyprogesterone – 11-deoxycortisol – cortisol/glucocorticoids
pathway from progesterone to androstenedione/androgens
progesterone – 17-hydroxyprogesterone – androstenedione/androgerns
what does zona glomerulosa secrete? What regulates its secretion?
aldosterone (mineralocorticoid)/ renin-angiotensin
what does zona fasciculata secrete? What regulates its secretion?
cortisol (glucocorticoid)/ACTH
what does zona reticularis secrete? What regulates its secretion?
dehydroepiandrosterone/ACTH
what is congenital adrenal hyperplasia (CAH)?
genetic enzymatic defects in cortisol synthesis. The adrenal cortex will still respond to ACTH, so hyperplasia will develop
what is a cause of CAH?
inborn defect to 21-hydroxylase. Its precursor is converted to androgen instead. Aldosterone lacking causes hypoaldosteronism. You will see hypotension and low Na+ in plasma)
what are cortisol and corticosterone?
glucocorticoids
what are aldosterone and deoxycorticosterone?
mineralocorticoids
what are DHEA, DHEA-S, androstenedione?
androgens
what does cortisol regulate?
intermediary metabolism
how are cortisol effects permissive?
cortisol doesn’t directly initiate metabolic or circulatory processes, but it is necessary to permit their full expression
how does ACTH regulate cortisol?
ACTH has a GCPR that is coupled with Gs, which activates adenylyl cyclase, cAMP, and in turn, PKA, which turns on the cholesteryl ester hydroxylase in the lipid proteins that turn cholesteryl esters into free cholesterol. Then the free cholesterol can go on to become cortisol.
where does ACTH come from?
anterior pituitary
What happens to cortisol once it is secreted?
it can become free cortisol in the plasma. Then, it will either bind to a cotisol-binding protein or it will be absorbed by tissue.
which proteins bind with cortisol in the plasma?
Corticosteroid-binding globulin or albumin
how large is corticosteroid-binding globulin? Where is it synthesized and secreted?
50 KD, in the liver
11Beta-hydroxysteroid dehydrogenase
enzyme used to convert cortisol to cortisone and vice versa
11beta-HSD 2
converts cortisol to cortisone
11beta-HSD 1
converts cortisone to cortisol
which is inactive? Cortisol or cortisone? Active?
cortisol is active/ cortisone is inactive.
