Schuler- Adrenal Gland Flashcards
blood supply to adrenal glands
suprarenal arteries
venous drainage of the adrenal glands
suprarenal veins
innervated by splanchnic nerves of sympathetic NS and the post-synaptic ganglia (Chromaffin cells)
synthesizes catecholamines
adrenal medulla
derived from neuroectoderm
adrenal medulla
derived from mesoderm
adrenal cortex
synthesizes glucocorticoids, mineralocorticoids, and androgens
adrenal cortex
3 layers of adrenal cortex
zona glomerulosa
zona fasciculata
zona reticularis
“GFR”
salt, sugar, sex
produced by zona glomerulosa
aldosterone
produced by zona fasciculata
cortisol
produced by zona reticularis
androgens
ACTH regulates the release of what
cortisol and androgens
hormones made in the cortex are all derived from ______
cholesterol
____transports cholesterol into mitochondria
StAR protein
_____ converts cholesterol to pregnenolone
cholesterol desmolase
____stimulates production and expression of StAR protein
ACTH
______ is the precursor to all of the hormones
pregnenolone
3 main enzymes important in cortisol synthesis
17alphaOH
21alphaOH
11betaOH
____secreted from hypothalamus stimulates ACTH synthesis and secretion
CRH
acts on adrenals and stimulates release of cortisol, androgens, etc
ACTH
____ inhibits CRH secretion
ACTH
____ inhibits both CRH and ACTH secretion
cortisol
highest concentrations of cortisol observed in ______
the morning
Body’s way of protecting kidney against cortisol is through _______ to inactivate it and allow for other hormones to bind to mineralocorticoid receptors (so aldosterone has opportunity to act)
11beta-HSD2
major active glucocorticoid in humans is ___
cortisol
____ circulates bound to transcortin and to albumin
cortisol
2 places where cortisol is inactivated
liver
kidney
someone w/ metabolic syndrome—-whole body ______likely higher than in a lean patient
cortisol
actions of ___ are widespread and important during periods of stress
glucocorticoids
Local ____ use is immunosuppressive and can cause overgrowth of yeast in mouth in pediatrics; local immune response is dampened and can make an infection worse
steroid
increases plasma glucose
Na+ reabsorption and K+ excretion
anti-inflammatory/immunosuppressive
lung development
circulatory integrity
cortisol’s major actions
cortisol’s effect on intermediate metabolism (catabolic hormone)
increase in plasma glucose
increases GFR
Na+ reabsorption and K+ excretion
increase osteoclast activity
cortisol effect on electrolytes
dose and duration is important to distinguish what effects of cortisol
anti-inflammatory
immune response
maintains CO
maintenance of responsiveness to NE
increase arteriolar tone
maintains endothelial barrier
cortisol mainting circulatory integrity
Surfactant synthesis; Increases lung fluid reabsorption by fetal lung
Clinical use of synthetic glucocorticoids to reduce incidence of respiratory distress syndrome in premature babies
cortisol effects on lung development
_____ of the adrenal gland expresses aldosterone synthase and produces aldosterone
zona glomerulosa
acts on mineralocorticoid receptors (MR) in the distal tubule of the kidney
Overall role is to help regulate blood pressure (increase Na+ and water retention (increases blood volume) and eliminate K+
aldosterone
____ protects mineralocorticoid receptor and allows aldosterone to act if there are elevated cortisol levels
11betaHSD2
increases GFR and inhibits sodium and water reabsorption
ANP
increased expression of ENaC Na channel
increased activity of ROMK K channel
aldosterone
RAAS: liver makes ____; renin is secreted by kidneys and cleaves to angiotensin I; ACE made by the lungs cleaves to ____
angiotensinogen
angiotensin II
adrenal androgens
DHEA and DHEAS
Major source of androgens in the female
adrenal gland (zona reticularis)
_____stimulates androgen synthesis in the zona reticularis
ACTH
adrenal androgens ______ feedback to inhibit ACTH release
do NOT
androgens are converted to estrogens in peripheral tissues by _______; this is the major source of estrogens in the male
aromatase
Decreased cortisol
Increased androgens (due to increased CRH and ACTH)
what deficiency?
21alphaOH deficiency
(congenital adrenal hyperplasia)
Sympathetic presynaptic release of acetylcholine stimulates the production and release of epinephrine and norepinephrine from________
adrenal medulla
plays role in fight or flight response
adrenal medulla
Blood supplied to the adrenal gland perfuses from the outer cortex to the inner medulla, allowing the adrenal medulla access to high concentrations of _____
adrenal steroids
direct neuroendocrine connection b/t sympathetic NS and _____
adrenal medulla
main product from adrenal medulla
Epinephrine
half life of _____ is REALLY short
catecholamines
used as clinical assay for adrenal
medullary function
VMA level in urine
___ and ___ bind to adrenergic receptors that are G protein and second messenger systems
Epi and NE
both ____ and ____ increase glucose synthesis
cortisol and Epi
____ is short term, and ____ is long term increase in plasma glucose
Epi; cortisol
inhibits aldosterone receptors. Used as a potassium-sparing diuretic
spironolactone
blocks cortisol action at the glucocorticoid receptor. Used in adrenal carcinoma and Cushings Syndrome.
Mifepristone
anti-fungal; long term use can block conversion of cholesterol to pregnenolone (precursor to all of the hormones)
ketoconazole
adverse reactions of glucocorticoid use
