The effects of Naja flava venom on blood coagulation

The effects of Naja flava venom on blood coagulation, fibrinogenolysis and fibrinolysis were studied in vitro. No coagulant activity could be detected, but the venom has a definite anticoagulant action. This may be through interference with the generation of thromboplastin and acceleration of its destruction after it is formed, probably because of the phospholipase A activity of the venom. The venom delays and decreases the generation of thrombin probably due to the anti-thromboplastin activity of the venom, but it has no effect on formed thrombin, or the thrombin-fibrinogen reaction. The venom has a direct fibrinogenolytic action but no action on formed fibrin, nor does it activate the intrinsic fibrinolytic system.