Inhibition of Fibrinolysis and Fibrinogenolysis in Man: Comparison of ε-Aminocaproic Acid and Kallikrein Inhibitor

Abstract

Inhibitor of kallikrein and trypsin (KI) extracted from bovine parotis was compared with ε-aminocaproic acid (EACA): both substances inhibit fibrinolysis induced with streptokinase. EACA is a strong inhibitor of fibrinolysis in concentrations higher than 0, 1 mg per ml plasma. The same amount and higher concentrations are not able to inhibit completely the proteolytic-side reactions of fibrinolysis (fibrinogenolysis, diminution of factor V, rise of fibrin-polymerization-inhibitors). KI inhibits well proteolysis of plasma components in concentrations higher than 2,5 units per ml plasma. Much higher amounts of KI are needed to inhibit fibrinolysis as demonstrated by our in vivo and in vitro tests. Combination of the two substances for clinical use is suggested. Therapeutic possibilities are discussed. ^* Present address: Division of Hematology, the Johns Hopkins Hospital, Baltimore, Maryland, U.S.A.