Kidney in potassium depletion. II. K/sup +/ handling by the isolated perfused rat kidney

Journal Article · Sun Mar 01 04:00:00 EST 1987 · Am. J. Physiol.; (United States)

OSTI ID:5935057

Hayashi, M; Katz, A I

In a companion paper the authors reported a large increment in Na/sup +/-K/sup +/-ATPase activity and (/sup 3/H)ouabain binding the inner stripe of outer medullary collecting tubules from K-depleted rats. To test the hypothesis that the increased number of Na/sup +/-K/sup +/ pumps in these animals may be involved in potassium reabsorption they examined the effect of ouabain on K excretion by isolated, perfused kidneys from rats fed a K-free diet for 3 wk. Kidneys from K-depleted rats retain potassium avidly, both the fractional (FE/sub K/) and absolute K excretion being approximately fivefold lower than in control kidneys. Ouabain (5 mM) increased FE/sub K/ in kidneys from each K-depleted rat; similar results were obtained when kidneys were perfused with low and high potassium concentrations. In contrast, ouabain produced a variable effect in control kidneys, that depended on the perfusate potassium concentration. In K-depleted rats amiloride did not significantly alter K excretion and did not block the ouabain-induced kaliuresis, suggesting that the latter is not due to enhanced secretion secondary to increased distal fluid delivery. These results provide evidence for ouabain-sensitive potassium reabsorption in kidneys of chronically K-depleted rats, and suggest an explanation for the increased Na/sup +/-K/sup +/-ATPase observed in such animals.

• Research Organization: Univ. of Chicago, IL
• OSTI ID: 5935057
• Journal Information: Am. J. Physiol.; (United States), Journal Name: Am. J. Physiol.; (United States) Vol. 252:3; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID ANHYDRASES
ALKALI METAL COMPOUNDS
ANIMALS
ATP-ASE
BIOLOGICAL EFFECTS
BODY
CARBOHYDRATES
CARDIAC GLYCOSIDES
CARDIOTONICS
CARDIOVASCULAR AGENTS
CATIONS
CHARGED PARTICLES
CLEARANCE
DRUGS
ENZYME ACTIVITY
ENZYMES
EXCRETION
GLYCOSIDES
HYDROLASES
IONS
KIDNEYS
LABELLED COMPOUNDS
MAMMALS
ORGANIC COMPOUNDS
ORGANS
OUABAIN
PERFUSED ORGANS
PHOSPHOHYDROLASES
POTASSIUM COMPOUNDS
RATS
RODENTS
STROPHANTHINS
TRITIUM COMPOUNDS
TUBULES
VERTEBRATES