Flashcards in Adrenal Deck (37)
Direct precursor for cortisol?
Direct precursor for Aldosterone?
Direct precursor for Androstenedione?
Angiotensin II is required for which adrenocortical hormone?
ACTH is necessary for conversion of cholesterol into _______.
Pregnenolone (precursor to aldosterone, cortisol, and androstenedione
17a-hydroxylase is necessary for formation of __________ and __________, and unnecessary for ________________.
Necessary for Cortisol and Androstenedione
Unnecessary for Aldosterone
A deficiency in 3B-hydroxysteroid dehydrogenase will prevent the formation of ________________ and _______________ and _____________
Aldosteron and Cortisol and Androstenedione will not be formed
Most cholesterol is created de novo.
Most cholesterol is bound to LDL
All adrenocortical steroids are made from ________________.
What happens to cholesterol we don't need right now?
It is esterified and stored in cytoplasmic vesicles until needed.
Glucocorticoids stimulate glycogenesis.
They stimulate Gluconeogenesis
Cortisol is what class of adrenocortical hormone?
Androstenedione is what class of adrenocortical hormone?
Aldosterone is what class of androcortical hormone?
Glucocorticoids can suppress the thymus.
They suppress the immune system this way
In a nutshell, glucocorticoids do what?
Tear things down so we can make and store as much glucose as possible.
Decrease immune system
Increase GFR (glomerular filtration rate)
Prolonged increase of GC often leads to
Dopamine, epinephrine, and norepinephrine are
Why are GC's essential for survival during fasting?
They stimulate GNG
Which of the following effects of cortisol DOES interfere with the body's inflammatory response?
A. Induce synthesis of lipocortin
B. Inhibit the production of interleukin 2
C. Inhibit the release of histamine
D. Block the release of epinephrine
A, B, and C all interfere with inflammation.
Blocking epinephrine does not interfere.
Name 2 drugs that inhibit GC
-Inhibits 11B-hydroxylase (prevents Aldosterone and Cortisol formation)
-used in diagnosis of adrenal insufficiency
-Inhibits cholesterol desmolase (the first enzyme converting cholesterol into all 3 hormone classes)
A patient with elevated levels of cortisol undergoes a dexamethasone suppression test. The high dose suppresses cortisol. What can be concluded?
The hypercortisolism is likely due to an anterior pituitary ACTH secreting tumor
A patient with elevated levels of cortisol undergoes a dexamethasone suppression test. The high dose does not suppress cortisol. What can be concluded?
Adrenal cortex cortisol secreting tumor
In a healthy person, a low dose of DXS will do what?
Decrease ACTH ----> Decrease cortisol
What stimulates aldosterone synthase?
Metyrapone will prevent the synthesis of what 2 hormones?
Aldosterone and cortisol by shutting down 11B-hydroxylase
In renal cells, the enxyme 11B-hydroxysteroid dehydrogenase performs what function?
Converts cortisol to cortisone
In a chromosomal XX female, masculinization is observed, including malformed external genitalia.
Urinalysis shows an elevation of 17-ketosteroids. These findings are indicative of what?
Cushing's SYNDROME vs Cushing's DISEASE
Syndrome: Chronic excess of GC due to overproduction of CORTISOL by ADRENAL CORTEX (or pharma overdose)
Disease: Excess GC due to hypersecretion of ACTH for a PITUITARY ADENOMA. Same symptoms as the syndrome except ACTH is high.