<prompt> Mechanism of action of Aspirin in MI is :Thromboxane A2 synthesis inhibitionThromboxane A2 synthesis stimulationAntagonist of adenosineStimulation of PGF2 synthesis  <response>: Ans is a Thromboxane A2 synthesis inhibition Ref Goodman Gilman, 10e, p. 1534; KDT 5e p. 572.Aspirin is used in MI because of its antiplatelet action.Antiplatelet action of aspirin: Aspirin blocks the production of thromboxane A2 by inactivating the enzyme cyclooxygenase. Cyclooxygenase is an enzyme that produces cyclic endoperoxide precursor of thromboxane A2. 