Histamine Metabolizing Activity of Dog Stomach and Intestine

Abstract

The gastric mucosa of the dog was studied for histamine-metabolizing activity using only a microgram of C¹⁴-histamine. The intestinal mucosa which contains much diamine oxidase (histaminase) was used as a control tissue. No evidence of diamine oxidase was found in the cell-free extracts of the gastric mucosa though much diamine-oxidase activity was present in the cell-free extracts of the intestinal mucosa. A small amount of histamine destruction not inhibited by aminoguanidine and semicarbazide occurred in minced tissue digests of both the fundic and pyloric mucosa.