title: Kinetics of urokinase-induced thrombolysis in a biphasic in vitro system.
abstract: The role and effect of added lys-plasminogen (lys-PLG) on urokinase-induced thrombolysis in an in vitro biphasic system were investigated. The kinetics of lysis of whole blood thrombi was followed in perfusion mediums of normal plasma, PLG-deficient plasma and normal saline using a high and a low concentration of urokinase (UK). The lysis of standard whole blood thrombi in whole blood perfusion mediums to which had been added UK alone or UK plus lys-PLG was compared to whole blood thrombi enriched with lys-PLG by incorporation during thrombus formation or by adsorption during perfusion. In addition, the kinetics of lysis of PLG-deficient fibrin thrombi perfused in PLG-deficient plasma or normal saline was studied when lys-PLG had been added to the thrombus, to the perfusion medium or to both thrombus and medium. In PLG-deficient plasma from which plasmin inhibitors had not been removed, thrombolysis was minimal even at a high concentration of UK. This effect could be neutralized, and to some extent, regulated, by lys-PLG enrichment of the medium. Both PLG-incorporated and PLG-adsorbed whole blood thrombi gave initial and sustained acceleration of UK-induced lysis in comparison with standard nontreated thrombi. It is concluded that in a blood-thrombus biphasic thrombolytic system induced by UK, there is interaction between the phases, and that PLG in both phases influences thrombolysis.
mesh_terms: D000328:Adult; D005342:Fibrinolysis / Q000187:drug effects*; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology; D010958:Plasminogen / Q000494:pharmacology; D013927:Thrombosis / Q000097:blood / Q000188:drug therapy*; D014568:Urokinase-Type Plasminogen Activator / Q000494:pharmacology*
chemical_list: D010446:Peptide Fragments; C018998:lysyl-plasminogen; D010958:Plasminogen; D014568:Urokinase-Type Plasminogen Activator