Renal 3 Flashcards
in the absence of vasopressin, the cortical and medullary collecting ducts are – to water
impermeable
without vasopressin, the osmolarity of tubular fluid would remain – than that of plasma
less
renin is secreted by – of kidneys
juxtaglomerular cells
renin – the removal of angiotensin I from angiotensinogen
catalyzes
conversion of Ang I to Ang II stimulates –
secretion of aldosterone from adrenal cortex
– directly innervates juxtaglomerular cells and stimulates renin secretion
renal sympathetic nerves
where are juxtaglomerular cells located at?
afferent arterioles
juxtaglomerular cells are sensitive to pressure within arterioles so they act as –
intrarenal baroreceptors
effect of reduced plasma volume and low blood pressure in kidney on baroreceptor cells
stretched less –> secrete more renin
layer of specialized epithelial cells located near the ends of the ascending loops of Henle
macula densa
macula densa are closely juxtaposed to –
afferent arteriole and juxtaglomerular cells
macula densa is a –
chemoreceptor
macula densa sense – in tubule flowing past it
Na+ and/or Cl- concentration
– concentration of Na+/Cl- cause macula densa to stimulate juxtaglomerular cells to secrete renin
decreased
three inputs controlling renin secretion
renal sympathetic nerves
juxtaglomerular cells as baroreceptors
macula densa as chemoreceptors
– CV pressure leads to increased vasopressin
decreased
– plasma osmolarity leads to increased vasopressin
increased
low plasma volume –> venous, atrial, and arterial pressures
decrease
which renal process is controlled for K+?
secretion
where does secretion of K+ occur?
cortical collecting ducts
effect of high plasma K+ on adrenal cortex
increase aldosterone secretion
increased plasma effect on cortical collecting ducts
increased K+ secretion and excretion
two major controls of aldosterone secretion
[plasma angiotensin II] and [plasma K+]
aldosterone induces – in luminal membrane of cortical collecting-duct cells
synthesis of Na+ and K+ channels
