Ion and water balance in isolated epithelial cells of the abdominal skin of the frogLeptodactylus ocellatus

Summary

Isolated epithelial cells were obtained from abdominal skin of the frogLeptodactylus ocellatus by a trypsination-dissection method. As estimated by nigrosin staining, the amount of damaged cells is only 6.6±0.7 per cent. When washed briefly after incubation the ionic concentrations in these cells were (mm): K⁺ 14.20±4.0; Na⁺ 15.8±1.8; and Cl⁻ 57.2±5.3. If they are not washed, the concentration of K⁺ remains essentially the same (131.2±1.4mm) but the Na⁺ concentration is much higher (38.5±0.9mm). It is shown that a large fraction of Na⁺ is contained in a compartment that is freely connected with the bathing solution. Ouabain (10⁻⁴ m) elicits a marked decrease of K⁺, a slight decrease of Cl⁻, and an increase of Na⁺ content. In an equal period, low temperature (3°C) produces a similar effect, although less marked than ouabain.