Response-size (displayed as area under the curve; AUC) of A: nitroglycerin (NTG) and B: sodium nitrite (SN)-induced dilatation in isolated aortic rings from treated (zofenopril, ZOF, n=10; lisinopril, LIS, n=8; N-acetylcysteine, NAC, n=8) and untreated rats with chronic myocardial infarction (MI, n=11) or no-MI (n=8). Dilatations were studied in presence of 10 μmol l−1 indomethacin. Data are mean±s.e.mean; # indicates P<0.05 versus MI.