The intrinsic activation of human factor X has been studied in a system consisting
of purified factors and in plasma. In both these systems factor Xa stimulated the
activation of factor X by factor IXa plus factor VIII This is due to the activation
of factor VIII by factor Xa. When this factor Xa is formed via the extrinsic pathway, the extrinsic factor X activator functions as a stimulator
of the intrinsic factor X activator.
Key words
Factor VIII - Factor X - Intrinsic pathway - Extrinsic pathway