The Nature of the Frog Skin Potential

TLDR

The isolated frog skin behaves as a sodium electrode on its outer surface and as a potassium electrode on its inward‑facing surface in the absence of penetrating anions. The authors propose that the frog skin potential arises from active sodium transport located at the inward‑facing membrane, hypothesizing that this transport is a forced exchange of sodium against potassium. Summary: 1, 2, 3.

Abstract

Summary. 1. The outside of the isolated frog skin in the absence of penetrating anions behaves over a wide range of concentrations as a sodium electrode, while the inward‐facing surface behaves like a potassium electrode. 2. A theory concerning the origin of the frog skin potential is put forward based on these observations and the assumption that the active transport of sodium is located at the inward‐facing membrane of the epithelial cells. 3. Reasons are given for the hypothesis that the active transport of sodium in reality is a forced exchange of sodium against potassium.