[Sodium and potassium ion transport in the skin of Rana temporaria frogs under anaerobic conditions].

Saturation of incubation media with argon completely inhibits the unidirectional transport of Na+ across the frog skin while the ion composition of the skin cells does not change at all. The maintenance of the intracellular concentrations of Na+ and K+ cannot be explained by an assumption that at anaerobic conditions the cell membrane permeability to monovalent cations is markedly decreased. For instance, an addition of ouabain to the serosa bathing medium saturated with argon results in increasing the intracellular concentration of Na+ and loss of cell K+ indicating that both Na+ and K+ can freely diffuse across the cell membrane down to their electrochemical gradients. The results obtained suggest that the Na+/K+ pumps involved in the mechanism of unidirectional Na+ transport are critically dependent on the respiration energy while the pumps responsible for the cell ion homeostasis can operate at the expense of glycolysis. Compartmentalization of the energy sources and their coupling to consumers may explain independent functioning of the two mechanisms of Na+ transport developed in the course of cell evolution.