[Binding of an acylated plasminogen activator-streptokinase complex with fibrin and the fibrinolytic response in vitro].

Affinity and fibrinolytic properties of streptokinase and two new preparations of acylated plasminogen-streptokinase activator complexes, produced by dissimilar procedures, were studied. Even after 1-min exposure, blood clot lysis carried out by the acyl activating complex was continued in blood plasma more than for 4 hrs, while the streptokinase produced blood clot lysis was accomplished within 1.5 hrs. After 1-min contact with clot in blood plasma the rates of lysis by streptokinase and these acylated plasminogen-streptokinase activator complexes types 1 and 2 constituted 23%, 37% and 63%, respectively, as compared with the rates detected during permanent contact of thrombolytics with blood clot. The activator properties of the thrombolytic agents itself and its stability in blood plasma were of importance even in similar affinity ability of free and acylated activating complexes.