Effect of potassium on secretion and potential of frog's gastric mucosa in Cl–-free solutions

Abstract

In previous work it was shown that the potential difference of the secreting mucosa bathed in Cl^–-free solutions (SO₄^– replacing Cl^–) is negative (nutrient side negative). In the present work it was found that an increase of the K⁺ concentration (K⁺ substituted for Na⁺) of the bathing fluid on the secretory side produced an increase in H⁺ secretory rate. The effect of voltage-clamping at zero and at +100 mv on the H⁺ rate, with various K⁺ concentrations in the bathing fluids, yielded results predicted by the electrogenic H⁺ theory, but not by a forced exchange concept.