Comparison of in Vivo Biochemical Effects of Human Urokinase Prepared from Urinary and Tissue Culture Sources

In patients with pulmonary emboli, resolution has been shown to be more rapid in those receiving urinary urokinase than in those receiving heparin alone. A different source of urokinase has now been developed, namely human kidney cells grown in tissue culture. In a randomized, multicenter trial, two groups of 15 patients with pulmonary embolism received either the urinary or tissue culture urokinase. Blood samples prior to, during and after treatment were compared with regard to biochemical changes in the plasma fibrinolytic system. Both agents caused strikingly similar rates, degrees and durations of response, as reflected in the whole blood euglobulin lysis time, unheated fibrin plate lysis zones, 125-I tagged clot lysis, plasma plasminogen, plasma clottable protein and serum fibrin/fibrinogen degradation products. Bleeding occurred in about 50% of both groups of patients, primarily from cutdown sites. The results clearly indicate that the pharmacologic effect of tissue culture urokinase was the same as that of urinary urokinase, and it is reasonable to expect that both materials will be equally effective in the hemodynamic and clinical aspects of patients with pulmonary embolism.