urinary / renal Flashcards
where is K+ predominately reabsorbed?
65% in the proximal tubules
3 x renal chagnes a/w severe hemorrhage
- afferent / efferent arteriole constriction
- increased filtration fraction
- Na retention by tubules
renin half life
80 mins
renin function
convert ANG > ANG-1
renin secretion controlled by x3
intrarenal baroreceptors
prostaglandins
Na content of prox / distal tubular fluid
4 x substances to increase renin secretion
decreased ecf
decreased bp
increased sympathetic output
prostaglandins
4 x factors to inhibit renin secretion
increased na / cl reabsorb across macula densa
increase afferent arteriolar pressure
angiotensin II
vasopressin
renal effects of angiotensin II
stim tubules to absorb Na
arteriolar constrict in both aff / eff
constict mesangial cells
extra-renal effects angiotensin II
potent vasoconstrictor adrenal cortex secrete aldosterone brain decrease sensitive baroreflex adh release + thirst reflex NA from sympathetic neurons
aldosterone produced where?
zona glomerulosa of adrenal cortex
aldosterone acts on ?
p cells in distal tubules n collecting ducts to increase Na reabsorb, in exchange for K and H
epithelium of salivary duct, sweat gland, small intestine, large intestine, rectum = reabsorb Na
aldosterone role?
to retain Na by increasing luminal Na channels,
increases sythesis i/o Na-K ATPase in basolateral membrane
more energy avail. for cells
aldosterone release stimulated by
ANG II
ACTH
K+
2 x basement membrane properties
pores of 8mm
negatively charged proteins lining the membrane
alcohol diuretic MOA
inhibits vasopressin secretion
