The Sound of Evolution
Warfarin
Mechanism of action:
Warfarin is a vitamin K antagonist. Warfarin inhibits vitamin K epoxide reductase complex 1 (VKORC1), blocking the regeneration of oxidized vitamin K into reduced vitamin K. Reduced vitamin K is an essential cofactor for gamma-glutamyl carboxylase. When it is deficient, clotting factors such as factors II, VII, IX, and X cannot undergo gamma-carboxylation properly, and therefore cannot effectively bind calcium ions and attach to phospholipid surfaces, ultimately inhibiting thrombus formation.
Reference(s):
1. Ansell J et al. (2004). The pharmacology and management of the vitamin K antagonists: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest.
2. Whitlon DS et al. (1978). Mechanism of coumarin action: significance of vitamin K epoxide reductase inhibition. Biochemistry.
3. Li T et al. (2004). Identification of the gene for vitamin K epoxide reductase. Nature.