[Effect of acetate on Na+-independent organic acid transport in the proximal tubules of the rat kidney].
At 20 degrees when active transport of an organic acid - fluorescein in superficial proximal tubules of surviving rat kidney does not depend on the external Na, the capability of acetate (as well as succinate and D,L-leucine) of stimulating the fluorescein uptake in the tubules was studied. As it turned out, acetate and leucine stimulated the fluorescein uptake at 120 mM of Na in the bath medium but had no effect at 10 mM of Na. Succinate has a biphasic effect on the fluorescein transport (stimulation at low succinate concentration), which does not depend on Na concentration in the medium. The effect of acetate disappears with the presence of ouabain in the medium. The stimulation of fluorescein uptake by acetate is accompanied by somewhat increased degree of reduction of cellular pyridine nucleotides. Pyridine nucleotides are reduced more markedly in the presence of ouabain or in the absence of Na from the bath medium. The disappearance of acetate effect on the fluorescein transport is explained by the fact of transition of cell mitochondria in the inactive state 4, due to the decrease in the level of cellular ADP when Na, K-ATPase is inhibited by ouabain or by diminution of tissue Na+ concentration.
D000085:Acetates / Q000494:pharmacology*; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002414:Cations, Monovalent / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005452:Fluoresceins / Q000378:metabolism*; D066298:In Vitro Techniques; D007687:Kidney Tubules, Proximal / Q000187:drug effects* / Q000378:metabolism; D007930:Leucine / Q000494:pharmacology; D008297:Male; D010042:Ouabain / Q000494:pharmacology; D051381:Rats; D012964:Sodium / Q000378:metabolism*; D013386:Succinates / Q000494:pharmacology; D019802:Succinic Acid
D000085:Acetates; D002414:Cations, Monovalent; D005452:Fluoresceins; D013386:Succinates; D010042:Ouabain; D012964:Sodium; D019802:Succinic Acid; D007930:Leucine
Vliianie atsetata na Na+-nezavisimyĭ transport organicheskoĭ kisloty v proksimal'nykh kanal'tsakh pochki krysy.