Warfarin exerts its anticoagulant effect by inhibiting which enzyme?
Answer and explanation
Correct answer: D. Vitamin K epoxide reductase
- Step 1: Warfarin blocks the recycling of vitamin K, so factors II, VII, IX and X and proteins C and S cannot be carboxylated. Step 2. Its effect is monitored with the INR. Answer: vitamin K epoxide reductase. Why not the others: heparin acts through antithrombin III, dabigatran inhibits thrombin directly and rivaroxaban inhibits factor Xa.
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