exam 2 adrenal hormones (quiz 2 info) Flashcards
what is essential for life?
what is not essential for life?
is= adrenal cortex
isnt= adrenal medulla
what 3 things does the adrenal cortex secrete
- corticosteroids (cortisol)
- mineralocorticoids (aldosterone)
- sex hormones (DHEA)
20-30% of adrenal gland tissue and helps to prepare individual to deal with emergencies
adrenal medulla
what does the adrenal medulla secrete in response to sympathetic NS stimulation?
EPI and NE
3 layers of cortex from most outer to inner:
outer:
1. zona glomerulosa-> mineralocorticoids
- zona fasciculata (largest)-> glucocorticoids
- zona reticularis-> androgens
what is mineralocorticoids secretion regulated by?
(zona glomerulosa)
renin-angiotensin-aldosterone system (RAAS)
(aldosterone)
what is glucocorticoids secretion regulated by?
(zona fasciculata)
hypothalamic-pituitary-adrenal axis (HPA)- CRH, ACTH
(releasing cortisol)
what is androgens secetion regulated by?
(zona reticularis)
HPA also
(DHEA- sex hormones)
what cells secrete catecholamines EPI and NE into the blood?
chromaffin cells
adrenal cortex secretes hormones that are made from
cholesterol
aldosterone increases renal tubular reabsorption of ____ and secretion of ____.
leads to an increase in EC fluid volume and mean arterial pressure
reabsorption of Na+
secretion of K+
aldosterone secretion is stimulated by:
angiotensin II (releases when blood pressure is low)
increase K+
decrease Na+
aldosterone has similar effects on sweat glands and salivary glands as renal tubules.
increases Na and secretes K
effect on sweat glands important to:
effects on salivary glands
conserve body salt in hot environments
conserve na during high rates of salivary secretion
enzyme released by the cells in the kidneys in response to a variety of stimuli ex. sympathetic nervous system:
what are these cells releasing this enzyme?
renin
cells are juxtaglomerular cells
angiotensin II does:
-aldosterone secretion
-vasoconstriction
-thirst stimulation
-ADH stimulation
how do we get to angiotensin II?
angiotensinogen (inactive) to angiotensin I via renin enzyme
angiotensin I to angiotensin II via ACE enzyme
what is the enzyme converting angiotensin I to angiotensin II and is produced by endothelium
ACE (angiotensin converting enzyme)
causes:
-adrenal adenomal (benign)
-adrenal hyperplasia
-adrenal carcinoma (malignment)
INCREASE IN aldosterone (ALD)
primary hyperaldosteronism (Conn’s Syndrome)
signs and symptoms of Conn’s syndrom (primary hyperaldosteronism)
-hypertension
-hypernatremia (high Na)
-headaches
-potassium depletion (hypokalemia)
^ fatigue and weakness
-polyuria
-hypokalemic alkalosis
-LOW plasma renin (due to negative feedback= hypertension and high ALD)
treatment options of primary hyperaldosteronism (Conn’s Syndrome)
-surgical removal of tumor or most adrenal tissue when hyperplasia is caused
-medication antagonism of mineralocorticoid receptor
caused by decreased blood flow and pressure in renal artery
secondary hyperaldosteronism
CHF
cirrhosis
nephrosis
renal artery stenosis (decrease in blood flow to a kidney so the kidney thinks blood pressure is low= increase in renin)
secondary hyperaldosteronism
what is the cause of secondary hyperaldosteronism
high plasma renin activity
signs and symptoms:
-hypernatremia w/ ecf volume expansion
-edema
-decreased cardiac output
-similar to primary hyperaldosteronism
BUT high renin and not low
secondary hyperaldosteronism