Acute changes of the Na-K-ATPase-activity in plasmamembranes of the isolated, cell-free perfused rat kidney.
The Na-K-ATPase-activity of the isolated, cell-free perfused rat kidney was investigated. Na-load and perfusion rate could be varied independently. The ATPase-assay was carried out on plasmamembranes (700-1200 g fraction) isolated and purified after 60 min perfusion. Both the specific Na-K-ATPase-activity and the fractional Na-reabsorption showed an indirect correlation with the Na-load as well as with the perfusion rate. The Na-K-ATPase-activity of plasmamembranes obtained from the isolated kidney at physiological Na-load fits well to control values prepared from unperfused control kidneys. The present data are in accord with the results of earlier micropuncture experiments, where acute saline loading diminished the rate of Na-absorption.
D000042:Absorption; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology* / Q000648:ultrastructure; D002463:Cell Membrane Permeability; D002474:Cell-Free System; D066298:In Vitro Techniques; D007552:Isotonic Solutions; D007668:Kidney / Q000201:enzymology* / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism; D008297:Male; D008854:Microscopy, Electron; D010477:Perfusion; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D012964:Sodium / Q000378:metabolism* / Q000494:pharmacology
D007552:Isotonic Solutions; D012964:Sodium; D000251:Adenosine Triphosphatases; D008274:Magnesium; D011188:Potassium