Overview This schematic shows the mechanism of thrombolysis. Plasminogen is cleaved into plasmin by tPA, urokinase, factor XIa, XIIa, and kallikrein. Plasmin then then degrades fibrin. Thrombolytics catalyze the formation of endogenous plasmin from plasminogen precursor login to view 1 more bullet Drugs login to view 4 more bullets Mechanism login to view 9 more bullets Clinical use login to view 5 more bullets Toxicity login to view 4 more bullets Antagonist login to view 3 more bullets