Effect of potassium depletion on ischemic renal failure.
The present study was carried out to examine the effect of potassium depletion in rat kidneys subjected to a temporary ischemic event produced by clamping of left renal artery. The postischemic kidneys of rats on a normal diet with adequate potassium intake showed an increase in H2O, Na and K excretion, with no change in inulin clearance whereas significant differences were found in potassium-deprived rats. Potassium depletion was brought about by dietary K deprivation for 10 days. K-depleted rats (serum K = 2.5 +/- 0.1 mEq/l) had a decrease in inulin clearance of the postischemic kidney from 1.01 +/- 0.10 to 0.43 +/- 0.05 ml/min (p less than 0.01), and a greater increase in fractional excretion of H2O, Na and K when compared to normal rats. The postischemic kidney from both normal and hypokalemic rats showed a decrease in Na-K-ATPase of the inner stripe of the outer medulla. These data indicate that short-term ischemia produces polyuria, increases natriuresis and kaliuresis, associated, at least in part, with a decrease in Na-K-ATPase in the inner stripe of the outer medulla (probably the thick ascending limb of Henle) and that K depletion potentiates ischemic renal failure.
Seguro
A C
AC
Laboratório de Pesquisa Básica da Faculdade de Medicina da Universidade de São Paulo, Brasil.
Shimizu
M H
MH
Monteiro
J L
JL
Rocha
A S
AS
D058186:Acute Kidney Injury / Q000150:complications / Q000209:etiology / Q000503:physiopathology* / Q000652:urine; D000818:Animals; D005919:Glomerular Filtration Rate; D007511:Ischemia / Q000150:complications*; D007668:Kidney / Q000098:blood supply* / Q000201:enzymology / Q000503:physiopathology; D008297:Male; D011188:Potassium / Q000652:urine; D011191:Potassium Deficiency / Q000150:complications*; D051381:Rats; D012078:Renal Artery Obstruction / Q000150:complications; D012964:Sodium / Q000652:urine; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium