Temperature dependence of membrane function. Disparity between active potassium transport and (Na+ & K+)ATPase activity.

Ouabain-sensitive K+ influx in mammalian erythrocytes exhibits far less temperature sensitivity than the ((Na+ & K+)ATPase prepared by hypotonic lysis from the same population of cells. The results are not in accord with lipid phase change as the critical mechanism of cold inhibition of intact pumps.