AIM:To investigate the effects of celecoxib,a selective cyclooxygenase-2 inhibitor,on antioxidative capability and apoptosis of cardiac myocytes after myocardial infarction.METHODS:24 New Zealand rabbits were divided into three groups randomly(8 in each group):sham-operated group(sham group),myocardial infarction group(MI group),celecoxib group(Cele group,10 mg kg-1?d-1,qd,with the drugs gastric gavage for six weeks).The NO concentration,total antioxidative capability(T-AOC),the activity of constitutive nitric oxide synthase(cNOS)and inducible NOS(iNOS)in cardiac tissue homogenate,adjacent to the infracted area,were detected.The pathological changes were observed by light microscope and electron microscopy.The expressions of Bcl-2 and Bax protein in myocytes were observed using immunohistochemistry,and the degree of apoptosis were examined by TUNEL.RESULTS:Cardiac tissue in MI group presented interstitial edema,fibroplastic proliferation,inflammatory cellular infiltration,and vacuolar degeneration in cardiac myocytes.The results of electron microscopy showed that myocytes presented more changes caused by ischemic injury:widened interspace of myofibril,disordered myofibrillae,focal lysis of myofilament,ectasia of sarcoplasmic reticulum.In Cele group,the pathological changes were light,the NO-_2/NO-_3 concentration,the activity of iNOS were lower(P