The Measurement of Fibrinolytic Activity with I¹³¹-labelled Clots. II. Application^[*]

Summary

1. The application has been described of a method, using I¹³¹-labelled clots as a substrate for the measurement of plasmin, urokinase and streptokinase.

2. With this method the inhibition of these fibrinolytic agents by plasma has been studied.

3. A striking difference in the fibrinolytic and fibrinogenolytic effect of urokinase and streptokinase was found. Urokinase appeared to be an effective fibrinolytic agent in the presence of plasma and gave rise to little fibrinogenolysis, while streptokinase appeared much less effective in this respect in the presence of plasma, but gave marked fibrinogenolysis.

^* This investigation was supported by a grant from the Organization for Health Research T. N. O.

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