High sodium diet and Na+-stimulated ATPase activities in basolateral plasma membranes from rat kidney proximal tubular cells.
The ouabain-insensitive, Na+-stimulated ATPase activity of kidney proximal tubular cells from rats fed a high Na+ diet for 4 months was increased approximately 70% when compared with control (normal diet) rats. The higher ATPase activity was not due to a change in the affinity of the system toward ATP, Mg2+ or Na+. This increase in Na+-ATPase activity may be due to either a higher number of pumps or to a higher turnover rate of the enzyme or both. The ouabain-sensitive, Na+, K+-stimulated ATPase activity, on the other hand, did not change with the high sodium diet. These results can be taken as evidence that the Na+,K+-ATPase and the Na+-ATPase of basolateral plasma membranes of proximal tubular cells from rat kidney are two different entities.
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D001485:Basement Membrane / Q000201:enzymology; D027682:Cation Transport Proteins; D006863:Hydrogen-Ion Concentration; D007687:Kidney Tubules, Proximal / Q000201:enzymology / Q000648:ultrastructure*; D008274:Magnesium / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000008:administration & dosage* / Q000494:pharmacology; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013696:Temperature
D027682:Cation Transport Proteins; D010042:Ouabain; D012964:Sodium; D000251:Adenosine Triphosphatases; C021838:sodium-translocating ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D008274:Magnesium; D011188:Potassium