Aspirin is used in the prophylaxis of myocardial infarction because it results in:: (A) Inhibition of thromboxane synthetase, (B) Inhibition of cyclooxygenase, (C) Decreased serum lipids, (D) Coronary steal phenomenon
Answer is B. Aspirin acts as an antiplatelet drug in MI. It inhibits cox enzyme and thus reduces the synthesis of TXA2. However it has no effect on the enzyme, thromboxane synthetase. Therefore, answer here is the inhibition of cox.