Role of Hepatic Blood Flow in Regulating Plasma Concentration of Antidiuretic Hormone after Hemorrhage.

Abstract

Summary Hemorrhage in splenectomized dogs under pentobarbital caused a decrease of hepatic blood flow (HBF) and an increase of antidiuretic hormone (ADH) concentration in the arterial plasma. The splanchnic extraction ratio for ADH remained at about 0.22 with all degrees of hemorrhage. Therefore as the HBF was reduced by hemorrhage, the splanchnic clearance of ADH decreased, and so did the percentage of total plasma ADH cleared by the splanchnic organs (mainly the liver) per unit time. After hemorrhage, the decrease in ADH clearance is not a major factor in causing the initial rapid rise in the circulating ADH concentration, but plays a part in maintaining this concentration at an elevated level.