The effect of vasopressin on hepatic arterial blood flow.

Vasopressin was successively infused into the hepatic and superior mesenteric arteries and a systemic vein, and its levels monitored by blood samples drawn from the portal and hepatic veins and a systemic vein. Blood flow was monitored in the hepatic and superior mesenteric arteries and in the ascending aorta. Hepatic blood flow was inversely correlated with mesenteric blood flow, rising about 50% above baseline levels during hepatic and systemic artery infusions and 96% during superior mesenteric artery infusion. Hepatic artery and systemic vein infusions caused a reduction in mesenteric flow about 20% less than that caused by direct superior mesenteric artery infusion.