The Role of Endogenous Histamine on Gastric Acid Secretion

Compound 48/80 decreased the secretion of acid of the frog's gastric mucosa with no significant change in the amount of histamine in the mucosa although the mast cells were almost completely degranulated. This result suggests that the mast cells of the frog contain little or no histamine. Triton X-100, a nonselective histamine liberator, released approximately 50% of the histamine in the mucosa primarily from the enterochromaffin-like cells with a corresponding increase in the secretion of acid. Pentagastrin, after either 48/80 or Triton X-100, stimulated the release of acid, although there was no further release of histamine. Therefore, pentagastrin can act directly on oxyntic cells to stimulate their secretion.