Acid secretion, potential, and resistance of frog stomach in K⁺-free solutions

¹ Department of Physiology and Biophysics, University of Louisville School of Medicine, and Department of Physiology and Biophysics, University of Alabama Medical Center, Birmingham, Alabama

The removal of K⁺ from the fluids bathing the in vitro frog gastric mucosa results in a decrease of the H⁺ secretory rate to zero, a marked increase in electrical resistance, a transient increase in potential difference (PD), and relatively little change in the K⁺ content of the mucosa. The effects of K⁺ removal are reversed by adding K⁺ either to the nutrient fluid (4 mm) or to the secretory fluid (104 mm). They are not reversed by voltage clamping (nutrient positive). Following the cessation of H⁺ secretion, the PD gradually decreases to a level that is low but still greater than zero. The PD under these conditions can be reversibly reduced to about zero by anoxia. It is concluded that the presence of K⁺ in certain regions of the mucosa is necessary for the functioning of the H⁺ and Cl^– mechanisms.

Key Words: gastric secretion • gastric potential • potassium on gastric secretion • potassium absence on stomach • potassium on PD and resistance • potassium content of stomach • anoxia on gastric PD in absence of K⁺ • hydrogen ion secretion, absence of K⁺ on resistance of frog stomach • voltage clamping on stomach • potassium lack on chloride transport

Submitted on July 10, 1964