McCarthy Renal Flashcards
the ____ arteriole is wider than the _____ arteriole
afferent wider than efferent
the glomerular capillary has higher ______ and ______ than systemic capillaries
higher pressure and higher permeability
there is a filtration of about ___ -___mL per min of plasma (free of cells and proteins) into bowman’s space
95-120
urine production is about __mL/min. why is this significant?
1mL/min, majority of fluid is being absorbed by tubular cells and returned to system circulation
what is Pgc, Pbs, and (pie)gc and which direction do they go?
Pgc: hydrostatic glomerular capillary pressure: favors filtration. force goes OUT of the capillary and INTO bowman’s space
Pbs: hydrostatic bowman’s space pressure: opposes filtration; force goes INTO capillary, OUT of bowmans space
(pie)gc: oncotic pressure of glomerular capillary; opposes filtration: force goes INTO capillary, OUT of bowman’s space
what is the strongest of the forces? (Pgc, Pbs and (pie)gc)? which has the most influence on change of net filtration?
Pgc has the strongest pressure around +45 mmHg
(pie)gc has the most influence… increases towards the end of the glomerular capillary to about -35mmHg (when filtration equilibrium is reached)
peritublar capillaries are …
low pressure with increased oncotic pressure
juxtaglomerular cells of the afferent arteriole respond to _________ or ________ and release renin
decrease perfusion pressure or increased sympathetic stimulation
what can cause decreased perfusion pressure of the kidney?
vole depletion or other diseases (like CHF)
what are the 5 angiotensin II effects?
- vasoconstriction
- increased aldosterone secretion
- increased proximal tubule Na+ reabs.
- increased ADH secretion (made in hypothalamus, secreted by post. pituitary)
- increased thirst
vasoconstriction action of angiotensin II at low vs high levels?
low: efferent constriction - increased GFR
high: afferent and efferent constriction- decreased GFR
aldosterone promotes reabsorption of what?
Na+ into the principal cells of the distal terminal tubule and collecting duct
renin with the production of angiotensin II and aldosterone causes what?
Na+ reabs. in the proximal tubule AND distal tubules and collecting duct
what do epinephrine and norepinephrine do?
increase renin secretion and increase prox tubule Na+ reabs.
what does ADH do?
increase H2O reabs. in the aquaporin cells of late distal tubule and collecting ducts
what is the best serum test for glomerular filtration rate? why?
creatinine: it is freely filtered, not reabsorbed.
what does furosemide do?
blocks Na+, Cl- and K+ reabs in the thick ascending loop.
how would you determine levels of ADH?
urine concentration: if its high then you have a high ADH. if urine is dilute then you have low ADH
what does thiazide do?
blocks Na+ and Cl- reabs in the first part of the distal convoluted tubule
what does spironolactone do?
blocks the Na+ reabs. and K+ excretion (b/c blocks the pump). It does so by blocking the effects of aldosterone
hypernatremia means what?
high salt in the blood (Na+), so high Na+ in the ECF
what would be the treatment for cerebral edema?
high Na+ conc. saline aka hyperosmotic (3%) to draw the water out of the brain
what are normal creatinine and BUN levels?
creatinine: 0.6 - 1.2
BUN: 6-20
ANP decreases what?
decreases sodium reabs in the DCT
Angiotensin II and SNS both increase what?
increase Na+ reabs. in PCT
