Editing Adrenal: Hyperaldosteronism (section)

== Renin-Angiotensin-Aldosterone-System (RAAS) ==

* '''Under normal physiologic conditions, renin release is stimulated by (low-volume, low-salt state):'''
*# '''Low renal perfusion pressure'''
*# '''Increased renal sympathetic nervous activity'''
*# '''Low sodium concentration sensed by the macula densa'''
* '''Renin then cleaves angiotensinogen to angiotensin I, which in turn is cleaved by angiotensin converting enzyme (ACE) to angiotensin II'''
* '''Angiotensin II'''
** '''Functions (2):'''
**# '''Potent vasoconstrictor'''
**#* '''In kidneys, angiotensin II causes vasoconstriction of efferent and afferent arterioles, with stronger effect on efferent arteriole.'''
**# '''Triggers the release of aldosterone'''
* '''Aldosterone'''
** Produced by:
*** Zona glomerulosa of adrenal gland
** '''<span style="color:#ff0000">Production'''
*** '''<span style="color:#ff0000">Stimulated by (3):'''
***# '''<span style="color:#ff0000">Angiotensin II (most potent stimulator)'''
***# '''<span style="color:#ff0000">Elevated serum potassium and decreased serum sodium'''
***# '''<span style="color:#ff0000">ACTH (much less potent stimulator)'''
***#* '''The zona glomerulosa is the only region of the adrenal cortex that does not atrophy on pituitary failure'''
*** Inhibited by:
**** Atrial natriuretic peptide
** '''Function:'''
*** '''Increases sodium reabsorption and potassium secretion''' in the distal nephron.
**** '''The increased sodium reabsorption increases total body volume.'''

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