The effect of heparin on the fibrinolytic activity of streptokinase-activated human plasma.

The effect of heparin on the clot lysis time of streptokinase-activated plasma was studied. Although the anticoagulaiit effect, the pre-incubation of the plasma-heparin mixture and great individual variations in the behavior of plasma made it difficult to obtain reproducible results, in general heparin stimulated clot lysis in small concentrations and retartled it in large concentrations. This two-way effect dependent on the concentration resembled tlie increased susceptibility of preformed fibrin to lysis observed earlier by other workers.Heparin seemed to have an influence upon the occurrence and lysis of paracongulation and detritus.