Prothrombinase

The prothrombinase complex is a composite of several factors block the plasmatic coagulation (secondary hemostasis ).

The complex consists of four factors:

• Stuart - Prower factor (factor X),
• Proaccelerin (factor V),
• Phospholipids and
• Calcium ions

The object of the prothrombinase complex is the activation of Factor II and therefore forms a central point of the coagulation cascade. He initially assembled on the surface of tissue factor - bearing cells. In the course of coagulation it can be found at the surface aktiviertet platelets.

Should be noted however, that the factor X by the initiation complex of tissue factor (TF) and factor VII is activated while the factor V is activated by thrombin that is already activated. This relationship, at first sight paradoxical can be explained that it is not a rigid schedule but a dynamic equilibrium of reactions in the plasma coagulation thereby.

Further Reading

• Bernd Pötzsch, Catherine Madlener: Hemostasis. Fundamentals, Diagnosis and Therapy Springer, 2010, ISBN 978-3642015434
• PN Walsh, SS Ahmad: Proteases in blood clotting. In: Essays in biochemistry. Volume 38, 2002, pp. 95-111, ISSN 0071-1365. PMID 12,463,164th (Review).
• AJ Gale, S. Yegneswaran et al: Characterization of a factor Xa binding site on factor Va near the Arg -506 activated protein C cleavage site. In: The Journal of biological chemistry. Volume 282, Number 30, July 2007, pp. 21848-21855, ISSN 0021-9258. doi: 10.1074/jbc.M702192200. PMID 17,553,804th
• ME Nesheim, JB Taswell, KG Mann: The contribution of bovine Factor V and Factor Va to the activity of prothrombinase. In: The Journal of biological chemistry. Volume 254, Number 21, November 1979, pp. 10952-10962, ISSN 0021-9258. PMID 500617th