Hepatic vascular response to epinephrine

Abstract

Hepatic hemodynamic events were measured before and after epinephrine administration in unanesthetized dogs in which the hepatic vessels had been previously catheterized. Comparisons were made of the response after a single intravenous injection at various doses and after a constant infusion of epinephrine; comparisons were also made between portal vein and femoral vein injections. After femoral venous injection of epinephrine (1–10 µg/kg) there was a marked increase in hepatic blood flow, roughly increasing with the size of the dose. With doses of 25 µg/kg or more, an initial increase in hepatic blood flow was followed by a decreased flow; in some instances death ensued. Epinephrine injected into the femoral vein produced a rise in the arterial blood pressure, followed by a rise in the portal vein pressure, portal-hepatic venous pressure gradient, and mechanical impedance across the hepatic venous bed. When injected into the portal vein under comparable conditions, epinephrine produced little or no change in hepatic blood flow or arterial pressure, but did produce a more rapid and pronounced increase in portal vein pressure, portal-hepatic pressure gradient and hepatic venous impedance.