In this sense we demonstrated for the first time a statistically significant increase in antioxidant enzyme activity (CAT and GPx) and decrease in superoxide anion levels, lipoperoxidation and protein carbonilation, along with an increase in GSH/GSSG in diabetic animals after myocardial infarction (DMI group) when compared to normoglycemic animals (MI group) (p < 0.05). Here, CAT is linked to myocardial infarction.