Activated protein C: Antithrombotic properties and influence on fibrinolysis in an animal model

The in vivo antithrombotic and profibrinolytic properties of human plasma protein C were investigated in a metallic coil induced thrombus model in the rat. Protein C, purified by immunoadsorption, was activated by thrombin and thereafter administered to the animals. Half-life of activated protein C (APC) revealed to be 15–16 min for the antigen, but only 7–8 min for the anticoagulant activity. Thrombus formation was reduced by APC in a dose-dependent statistically significant manner. A profibrinolytic effect of APC was observed when administered in combination with human tissue plasminogen activator. APC alone caused a reduction of thrombus weight. However, both effects were statistically not significant.