Histamine metabolizing activity of the stomach and intestine of the rat

Abstract

The squamous and glandular stomach and the small intestine of rats were studied for histamine-metabolizing activity, using 1 µg of C¹⁴-histamine as the substrate. The intestinal mucosa which contains much diamine oxidase (DO) (histaminase) was used as a control tissue. The squamous stomach metabolized approximately 70%; the glandular stomach, 40%; and the small intestine, 92% of the histamine. After adding the DO inhibitors, aminoguanidine and semicarbazide, to the minced tissue digest of all three tissues, approximately 12% of the histamine was still destroyed or unaccounted for.