The relationship of K+ efflux at the inner surface of the isolated frog skin epithelium to the short circuit current.
Isolated frog skins (without chorion) were incubated with 42K+ Ringers' solution, bathing the internal surface for 2 h. All the K+ contained in the frog skin was equilibrated in specific activity with external 42K+. The kinetics of the washout of 42K+ from the internal surface of the skin exhibits one fast and one slow exponential component. Amiloride reduces the release of 42K+ corresponding to both components without affecting the K+ content of the skin. Ouabain increases the loss of 42K+ of the slow component by 200%. Since the total K+ in the skin decreases to 25% of its original value both compartments are affected. The results suggest that two distinct functional compartments exist defined by two 42K+ release ratios and that because of the large K+ contents of these compartments both are intracellular. The relation with the transepithelial Na+ transport and the morphological identification of these compartments is discussed.
D000818:Animals; D001001:Anura; D001692:Biological Transport / Q000187:drug effects; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D007700:Kinetics; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*; D011896:Rana temporaria; D012867:Skin / Q000187:drug effects / Q000378:metabolism*
D010042:Ouabain; D011188:Potassium