Specific fibrinolytic properties of different molecular forms of pro-urokinase from a monkey kidney cell culture.
The specific fibrinolytic properties of both high molecular weight (55 kd) and low molecular weight (30 kd) pro-urokinase from a monkey kidney cell culture were evaluated in a plasma clot lysis system and compared with those of human urokinase. The system was composed of a radiolabelled plasma clot immersed in plasma containing the fibrinolytic agent. On unit base, 55 kd pro-urokinase was approximately 1.5 times more effective in lysing the clot than 30 kd pro-urokinase and equally effective as urokinase. In contrast to urokinase, both pro-urokinase forms induced clot lysis without degrading fibrinogen in the surrounding plasma. However, a considerable activation of the fibrinolytic system in the plasma occurred as a large amount of alpha 2-antiplasmin was consumed, indicating that pro-urokinase was not fully fibrin-specific. Quenching antibodies against tissue-type plasminogen activator (t-PA) added to the plasma clot lysis system retarded but did not prevent pro-urokinase-induced clot lysis. This indicated that not only was t-PA in plasma involved in the activation of pro-urokinase (probably via plasmin), but that an additional mechanism also existed.
D000818:Animals; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism; D005341:Fibrinolysin / Q000378:metabolism; D005342:Fibrinolysis; D066298:In Vitro Techniques; D007668:Kidney / Q000201:enzymology; D008252:Macaca fascicularis; D008970:Molecular Weight; D010960:Plasminogen Activators / Q000378:metabolism*; D013379:Substrate Specificity; D010959:Tissue Plasminogen Activator / Q000378:metabolism; D014568:Urokinase-Type Plasminogen Activator / Q000378:metabolism*; D000979:alpha-2-Antiplasmin / Q000378:metabolism
D004792:Enzyme Precursors; D000979:alpha-2-Antiplasmin; D005340:Fibrinogen; D010960:Plasminogen Activators; D010959:Tissue Plasminogen Activator; D005341:Fibrinolysin; D014568:Urokinase-Type Plasminogen Activator