What is a primary mechanism of action of anticoagulants like Heparin?

The primary mechanism of action of anticoagulants such as Heparin involves the inhibition of thrombin and factor Xa. Heparin is an indirect anticoagulant that enhances the activity of antithrombin III, a naturally occurring anticoagulant protein. When Heparin binds to antithrombin III, it significantly increases the inhibition of thrombin as well as factor Xa, which are crucial components of the coagulation cascade.

Thrombin is responsible for converting fibrinogen to fibrin, a key step in blood clot formation. By inhibiting thrombin, Heparin effectively prevents the formation of fibrin clots. Factor Xa plays a central role in the common pathway of coagulation by converting prothrombin into thrombin. Inhibiting factor Xa also contributes to reducing thrombin levels, thus further hindering clot development.

While other anticoagulants may work through different mechanisms, the actions of Heparin predominantly focus on disrupting the activity of thrombin and factor Xa, making this option the most accurate in describing its primary action.