The alpha2-plasmin inhibitor levels in liver diseases.

Concentrations of alpha-2 plasmin inhibitor, which is a primary and fast-reacting inhibitor of plasmin, were measured immunochemically in sera of patients with liver diseases and compared with normal controls. Serum level of alpha2-plasmin inhibitor was significantly decreased in liver cirrhosis and other severely affected liver diseases. The decrease appeared to be dependent upon the extent of liver damage, and the level of alpha2-plasmin inhibitor was closely correlated with parameters of liver functions of protein synthesis such as albumin concentration and cholinesterase activity in serum. The level of alpha2-plasmin inhibitor was fairly well correlated with the fibrinolysis inhibitor activity of serum. In contrast to alpha2-plasmin inhibitor, levels of alpha2-macroglobulin and alpha1-antitrypsin were increased significantly in liver cirrhosis. It was suggested that the reduction of alpha2-plasmin inhibitor level contributes substantially to the increased fibrinolytic activity observed in liver cirrhosis.