Free protein S itself has anticoagulant effects: it inhibits the prothrombinase complex (factor Xa, factor Va, and phospholipid), which converts prothrombin to thrombin, and the tenase complex ...

Factor Xa, factor Va, and calcium form a prothrombin-activating (prothrombinase) complex, which promotes the conversion of pro-thrombin to thrombin.

That's what aspirin therapy is." Prothrombinase, which catalyzes prothrombin conversion to thrombin, contains the blood coagulation proteins, factors Xa and Va.

News & Views Published: 04 April 2013 Blocking bleeding: reversing anticoagulant therapy Jack Ansell Nature Medicine 19, 402–404 (2013) Cite this article ...