Vascular perfusion of an intestinal segment in the catfish (Ictalurus melas, R): demonstration of the vasoactive effects of mammalian VIP and of gastrointestinal extracts from teleost fish.

Through the middle mesenteric artery and the hepatic portal vein it is possible to perfuse specifically a small part of the catfish midgut. Using a tested VIP extraction procedure it is shown that trout and catfish extracts of oesophagus, stomach, midgut and hindgut induce a vasodilation similar to that of porcine VIP. The importance of the vasodilatory response depends on the level of perfused VIP and extracted tissue.