Abstract
The possibility of a Na+/H+ exchange mechanism in the presence of NaF was studied in acid secreting and non-acid secreting stomachs of anesthetized cats. In non-acid secreting stomachs, although H+ loss and Na+ gain were both pH related, there was no constant relationship between the two. The H+ loss in non-acid secreting stomachs could not account for the H+ loss in histamine stimulated stomachs. In acid secreting stomachs the Na+ or neutral Cl- gain was only of the order of 50% of the H+ loss, and in the presence of isosmolal NaNO3, NaF produced the same reduction in H+ but with a markedly suppressed gain in neutral chloride. The NaF-induced reduction in H+ output was accompanied by reductions in the total Cl- output, the K+ output and the mucosal blood flow. The reduction in H+ output from histamine-stimulated stomachs is largely a result of inhibition of secretion.