Mesenteric vascular effects of prostaglandins F2 alpha and B2. Possible advantages over vasopressin in control of gastrointestinal bleeding.

Mesenteric vascular effects of prostaglandins B2 and F2 alpha were studied and compared to those of vasopressin in the dog, cat and baboon. Vasopressin reduced superior mesenteric blood flow (SMBF) 80-100%, and significantly increased hepatic arterial blood flow and systemic arterial pressure. Prostaglandin B2 produced vasodilatation at low doses and biphasic vasodilatation/vasoconstriction at high doses. Prostaglandin F2 alpha elicited only vasoconstriction, reducing SMBF, left gastric, and inferior mesenteric blood flow 80-100%. Systemic arterial pressure was not significantly changed. Thus, vasopressin and prostaglandin F2 alpha are equally effective mesenteric vasoconstrictors. Because of reduced systemic effects, prostaglandin F2 alpha has excellent potential as a mesenteric vasoconstrictor to control gastrointestinal hemorrhage.