Interactions of ε-Aminocaproic Acid with the Thrombin Clotting and Fibrinolytic Systems

Abstract

SEVERAL, reversible inhibitors of plasmin have been found to protect the latter from irreversible combination with antiplasmin within appropriate limits of time and concentration parameters. However, ε-aminocaproic acid (EAC) and several related compounds appeared to potentiate the destruction of plasmin by antiplasmin, even though they were able to stabilize the enzyme against autodigestion in the absence of antiplasmin^1,2. Because of the complexities of the two-phase model system used for these examinations, it was difficult to decide whether the results could be explained entirely on a kinetic basis, or whether in addition some unique reaction involving EAC and related structures could be taking place. The present investigations of a single-phase clot lysis system provided unexpectedly dramatic visual evidence in favour of the latter possibility.