Heparin, heparin-activated enzymes and platelets.

This review summarises evidence supporting the view that the therapeutic anticoagulant properties of heparin are related to its physiological function in the organism, especially its activation of lipoprotein lipase and lecithinase. The conflicting results obtained from studies of the effect of heparin on platelet function are discussed, together with reasons for these differences of opinion. Finally, a hypothesis which links heparin, heparin-activated enzymes and platelet function is proposed, this hypothesis being complementary to the current views concerning the activation by heparin of the inhibitor of activated factor X.