Adrenals - Study Guide Info Flashcards
What are the general functions of the adrenal cortex?
- Protect against sodium and potassium loss
- fuel metabolism
- androgens (sex hormones) also play role
What general hormone type is dealt with in the adrenal cortex?
adrenal steroids
LDL’s attach to receptors called ____ ___ on adrenocortical membranes to form vesicles with _________ to then release cholesterol and synthesize with hormones.
- coated pits
- lysosome
CRH released from _______, which simulates ACTH, then stimulates LDL’s causing _______ to enter mitochondria.
- hypothalamus
- cholesterol
Cholesterol is cleaved by _______ _______ to synthesize pregnenolone.
- cholesterol desmolase
What is the rate limiting step for all cortex hormones bound in plasma by cortisol-binding globulin or transcortin?
pregnenolone
Zona Glomerulosa is associated with major hormone type from the adrenal cortex?
Mineralocorticoid (affects sodium/potassium concentrations)
What mineralocorticoid from the Zona Glomerulosa functions to preserve vascular volume?
Aldosterone
Control of the synthesis of Aldosterone is mediated by what organ?
Kidney
In the zona glomerulosa, what is a major hormonal signal for the increased production of Aldosterone?
Angiotensin II
Cells of the zona glomerulosa are very sensitive to changes in concentration of what ion?
Potassium
Due to increase in Angiotensin II, Aldosterone increases reabsorption of sodium into extra cellular fluid…Potassium then moves out of system by ______ _____ & ATPase control
principle cells
What are the 4 factors that play a role in aldosterone secretion by the zone glomerulosa?
- Increased potassium
- Increased angiotensin II
- Increase in sodium concentration in extracellular fluid slightly decreases aldosterone secretion
- ACTH is necessary for aldosterone but little control in the rate of secretion
What is the condition associated with EXCESS aldosterone in the zona glomerulosa?
Hypokalemia (low potassium) = Muscle weakness
What is the condition associated with DECREASED aldosterone in the zona glomerulosa?
Hyperkalemia (high potassium) = Tetany (muscle spasms)
What are the 2 types of diabetes insipidus associated with decreased aldosterone levels?
Central and Nephrogenic diabetes insipidus
What is the middle and widest layer of the adrenal cortex and secretes glucocorticoids?
Zona Fasciculata
Zona fasciculata is associated with major hormone type from the adrenal cortex?
glucocorticoids