Analysis of fibrinolysis by the use of epsilon-aminocaproic acid: preliminary report.

P LASMIN, a proteolytic and fibrinolytic enzyme of blood, is present normally as an inactive precursor, plasminogen, in the circulating blood. In various pathologic conditions plasminogen may convert into active plasmin in vivo. Recently it has been reported by Okamoto et al. that e-aminocaproic acid (ACA ) has a potent inhibitory activity in the dissolution of fibrin by plasmin when activated by streptokinase ( 5K) in plasma. It is one of the purposes of this communication to determine the effect of this compound upon the fibrinolytic process. The present report is concerned particularly with re-examination of the theories which have been proposed to explain the mechanism of fibrinolysis. Evidence obtained here indicates that certain newly mentioned products, metafibrin and fibrinolysopeptide, may be split off from fibrin in the early phase of the fibrinolytic process.