Thrombin inhibitors from different animals.

Venous and arterial thromboembolic diseases are still the most frequent causes of death and disability in high-income countries. Clinical anticoagulants are inhibitors of enzymes involved in the coagulation pathway, such as thrombin and factor X(a). Thrombin is a key enzyme of blood coagulation system, activating the platelets, converting the fibrinogen to the fibrin net, and amplifying its self-generation by the activation of factors V, VIII, and XI. Thrombin has long been a target for the development of oral anticoagulants. Furthermore, selective inhibitors of thrombin represent a new class of antithrombotic agents. For these reasons, a number of specific thrombin inhibitors are under evaluation for possible use as antithrombotic drugs. This paper summarizes old and new interests of specific thrombin inhibitors described in different animals.