Thrombolytic properties of an inactive proenzyme form of human urokinase secreted from human kidney cells.
The relative fibrin-binding, fibrinolytic and fibrinogenolytic properties of single-chain pro-urokinase, an inactive proenzyme form of human urokinase purified from cultured human kidney cells, and urokinase were compared. The affinity of single-chain pro-urokinase for fibrin was much higher than that of urokinase. In Vitro thrombolytic studies showed that single-chain pro-urokinase is approximately three times more potent in fibrinolysis than urokinase and that it does not degrade fibrinogen in the plasma at a concentration, at which complete plasma clot lysis takes place; whereas, urokinase extensively degrades the fibrinogen in the plasma. These specific, potent thrombolytic properties of single-chain pro-urokinase seem to be due to its high affinity for fibrin and to its conversion from the inactive single-chain form to the active two-chain form on the thrombus by the catalytic amount of plasmin generated during coagulation. This single-chain pro-urokinase obtained from human kidney cells by tissue culture should prove advantageous than urokinase in thrombolytic therapy.
D001345:Autoradiography; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004792:Enzyme Precursors / Q000378:metabolism*; D005343:Fibrinolytic Agents / Q000378:metabolism*; D006801:Humans; D007668:Kidney / Q000378:metabolism*; D008968:Molecular Conformation; D010960:Plasminogen Activators / Q000378:metabolism*; D014568:Urokinase-Type Plasminogen Activator / Q000378:metabolism*
D004792:Enzyme Precursors; D005343:Fibrinolytic Agents; D010960:Plasminogen Activators; D014568:Urokinase-Type Plasminogen Activator