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Flashcards in RENAL PHYSIOLOGY Deck (19):

what three things control renin secretion

Intrarenal baroreceptors
Sympathetic input
Macula densa feedback


what does angiotensin II and name at least two things that it does

it is a vasoconstrictor
stimulates the release of aldosteron
stimulates sodium bicarb reabsorption in the proximal tubule
preferentially constricts efferent arterioles


what does aldosterone do to the kidneys

promotes Na reabsorption and K excretion in the proximal tubule


in severe volume depletion what are the major stimuli leading to major output effects and what does this cause the kidney to do

Major stimuli:
- inc plasma osm
- decreased blood volume
- decreased blood pressure

Major output:
- sympathetic stimuli
- increase in RAAS

- reduced excretion of salt and water
- increased retention


in acute volume expansion what are the major stimuli leading to major output effects and what does this cause the kidney to do

major stimuli:
- change in atrial volume and pressure

major outputs:
- decreased sympathetics

- massive dieresis and diluted urine


what type of cells line the proximal convoluted tubule

simple cuboidal epithelial cells with prominent brush borders of microvilli


which cell type lines the descending limb and the thin ascending limb of the loop of Henle

simple squamous epithelial cells


Which cell type lines the thick ascending limb of the loop of Henle

simple cuboidal to low columnar epithelial cells


which cell type lines the DCT

simple cuboidal epithelial cells


which cell type lines the last part of the DCT and collecting duct

simple cuboidal epithelium consisting of principal cells and intercalated cells


what do principal cells do in the DCT

mediate the collecting ducts influence on sodium and potassium balance via sodium and potassium channels on the cells apical membrane


which hormone determines expression of sodium channels on the surface of the principal cells in the collecting duct



what do the intercalated cells in the collecting ducts participate in

acid base homeostasis


how and where is glucose reabsorbed in the nephron

in the PCT
through Na-glucose symporters in the apical membrane
then through basolateral membrane through glucose facilitated diffusion transporters


what are the membrane transporters located in the apical membrane of the cells lining the thick ascending lumb of the loop of henle

Na-K-2Cl symporters


what does PTH stimulate in the early DCT

reabsorption of calcium ions


what is reabsorbed in the early DCT

sodium and chloride ions
NaCl symporters on apical membrane


where is the juxtaglomerular apparatus

between afferent and efferent arterioles in the juxtaposition ofthe DCT


what does the macula densa do

senses sodium conc and tubular fluid flow
feeds back to the juxtaglomerular cells