interactions

Last reviewed 01/2018

There is a close association between platelets, endothelium and the coagulation cascade:

• released on activation, platelet factor 3 - PF3 - facilitates factor IXa, so enhancing the intrinsic pathway
• PF3 facilitates the conversion of prothrombin to thrombin directly
• small amounts of coagulation factor are found within platelets e.g. V and XI, as well as fibrinogen
• platelet plasma membranes have receptor sites for factors e.g. V and X, so localising the deposition of fibrin
• damaged endothelium can trap and activate factors IX, X and V
• normal endothelium prevents thrombosis by the production of mediators such as prostacyclin GI2, heparin and plasminogen activator