adrenal gland hormones Flashcards
hormones of the adrenal cortex are called
mineralocorticoids and glucocorticoids (androgens)
mineralocorticoids
aldosterone
desoxycorticosterone
glucocorticoids
cortisol and corticosterone
hormones from the adrenal medulla
epinephrine
norepinephrine
(catecholamines)
the adrenal cortex is the source of ____
steroid hormones, esp cortisol, androgens, and aldosterone
zones of the adrenal cortex
zona reticularis, zona fasciculata, zona glomerulosa
steroid hormones like vitamin D derive from? and are ____ soluble?
from cholesterol
fat soluble
cholesterol is made in the—
liver
synthesis of aldosterone
acetate–> cholesterol–> pregnenolone–> progesterone–>aldosterone
synthesis of cortisol
acetate–> cholesterol–> pregnenolone–> progesterone or 17-OH-pregnenolone–> 17-OH-progesterone–> cortisol
synthesis of dehydroepiandrosterone
acetate–> cholesterol–> pregnenolone–> 17-OH-pregnenolone–> dehydroepiandrosterone
what is the branch point for synthesis of steroids?
pregnenolone
relative effects on mineral metabolism from mineral corticoids
aldosterone 90%
deoxycorticosterone 2%
corticosterone slight
cortisol slight
overall effectiveness of endogenous glucocorticoids
cortisol 95%
corticosterone 4%
overall effectiveness of synthetic glucocorticoids
prednisone 4X cortisol
methylprednisone 5X cortisol
dexamethasone 30X cortisol
_____ has the highest affinity
cortisol-binding globulin
albumin
binds corticoids
—— % glucocorticoids are bound is plasma proteins; half life —- mins
90-95%
60-90 mins
about 60% aldosterone bound; half life 20 min
how do steroids enter cell?
diffusion and then bind to receptors in cytoplasm
response elements
specific DNA sequences where the hormone-receptor complex binds in the nucleus
how does the hormone-receptor complex exert its effects?
altering transcription of genes–> mRNA which directs ribosomal synthesis of proteins
Nearly all the cells in the body have ______ so the effects of ______ are widespread
nearly all cells in the body have glucocorticoid receptors so the effects of cortisol are widespread