Adrenal Hormones Flashcards
Chromaffin cells in the medulla secrete _(2)
Epi and norepi
The cortex zona glomerulosa secretes _
mineralocorticoids (aldosterone)
The cortex zona fasciculata secretes _
glucocorticoids (cortisol) and androgens
The cortex zona reticularis secretes _
Androgens and glucocorticoids
Blood flow patterns in the adrenal glands ensure that blood flows from _ to _ ([cortex/medulla]
Cortex to medulla
The catecholamines mediate the short term fight or flight responses. One area where they have no direct effects is _
CNS. Cannot cross BBB
What types of receptors to catecholamines bind? What are the receptors of NE? Epi?
GPCR
NE- a1, a2, b1
Epi - a1, a2, b1, b2
Of the catecholamine receptors, which is inhibitory? which binds epi with highest affinity?
a2
b2
The rate limiting step of catecholamine synthesis is mediate by what enzyme? What order are catcholamines made?
Tyrosine hydroxylase
DA-NE-Epi
What is a pheochromocytoma? What are symptoms?
A tumor of chromaffin cells oversecreting catecholamines
Sudden onset “fight/flight” symptoms
The precursor for mineralocorticoids, glucocorticoids and sex steroids is _
Cholesterol
The protein that chaperones cholesterol to the mitochondria is _
StAR
The rate limiting step for steroid hormone synthesis is the production of _. It is catalyzed by what enzyme? Where does this occur (2)?
Pregnenolone synthesis
Desmolase
Mitochondria and ER
In the gonads, what enzyme converts testosterone to estradiol?
Aromatase
What enzyme converts testosterone to dihydrotestosterone?
5-alpha-reductase
Between aldosterone and cortisol, which has a shorter half life? Why?
Aldosterone, because it circulates in free form, vs. cortisol circulates bound to cortisol binding globulin
The major effect of aldosterone is _. What life threatening condition can occur in the absence of aldosterone?
Na rebsorption, K+ secretion
Hyperkalemia
Aldosterone escape refers to _
The ability of the body to stop aldosterone from continually increasing extracellular volume
Cortisol and aldosterone can bind the same mineralocorticoid receptor. What prevent this from occuring?
Enzyme 11-beta-HSD2 is expressed in aldosterone responsive tissues, hydrolyzes cortisol to cortisone
The 2 major + regulators of aldosterone release are_. The major - regulator is _
High plasma K+, Renin-Ang-system
ANP
Increased gluconeogenesis, decreased cellular glucose utilization, increased blood glucose are all effects of _
Glucocorticoids
Increased fat mobilization from arms and legs, decreased protein synthesis, anti-inflammatory effects are all effects of _
Gluco-corticoids
Decreased lymphocyte proliferation and decreased cytokine synthesis are effects of _
Glucocorticoids
ACTH sequences are contained within the same peptide fragment containing _ (2)
POMC
MSH
