DEMONSTRATION OF UROKINASE‐RELATED FIBRINOLYTIC ACTIVITY IN HUMAN PLASMA

Abstract
Various preparations of anti‐urokinase antibodies were found to quench a part of the plasma fibrinolytic activity. This part was also inhibited by a specific, urokinase inhibitor isolated from placenta. These observations indicate that plasma contains a urokinase‐related immuno‐reactivity. This activity was found to belong to the factor XII‐independent proactivator system.