Effects of endothelin-1 on hepatic blood flow

Endothelin-1 belongs to a family of potent vasoconstrictors, recently isolated from endothelial cells. Endothelin-1 has a variety of hepatic effects and hepatic clearance from the circulation is important. Elevated plasma concentrations of Endothelin-1 are found after orthotopic liver transplantation and in cirrhosis with ascites. This study in piglets on hepatic bloodflow was designed to compare differences in effects between central venous and intraportal injection of endothelin-1, and to evaluate effects of repeated injections. Central venous injection of endothelin-1 caused a larger reduction in portal vein flow, while intraportal injection caused a larger increase in portal vein pressure. Repeated injections resulted in a reduction in portal vein flow and an increase in portal vein vascular resistance.