What are the effects of heparin on platelets and endothelial cells?
Heparin can bind to platelets and, depending on the experimental conditions, can either induce or inhibit platelet aggregation. High-molecular-weight heparin fractions with low affinity for AT have a greater effect on platelet function than low-molecular-weight fractions with high AT affinity. Heparin can also interact with endothelial cells, which may contribute to heparin-induced bleeding by mechanisms independent of its anticoagulant effect. 