Comparison of alterations in the histamine-diamine oxidase system during acute intestinal ischaemia in pigs, dogs and rabbits; evidence for a uniform pathophysiological mechanism?

Among various vasoactive substances histamine was also suggested to induce circulatory arrest following superior mesenteric artery occlusion. Thus the involvement of the histamine-diamine oxidase system was studied in intestinal ischaemia using three animal species. In pigs, dogs and rabbits aminoguanidine, the specific inhibitor of diamine oxidase, shortened the survival time after mesenteric infarction. Under these conditions the diamine oxidase activity in the intestinal wall was reduced in animals treated by saline whereas the histamine content was not altered significantly. Plasma histamine levels were increased considerably in the portal vein of pigs during the revascularization period if the animal were pretreated by aminoguanidine. Similar findings were obtained in dogs. It was concluded that in all three species investigated the diamine oxidase protects the organism against the deleterious effects of at least one of its vasoactive substrates-histamine.