SOD1 and myocardial infarction: SOD activity level was reduced in the heart of MI rats (142.81 ± 12.75 vs. 365.25 ± 25.88 U/mg protein), and alarin administration enhanced the decrease of SOD activity level in the heart of MI rats (237.82 ± 16.52 vs. 142.81 ± 12.75 U/mg protein) (Fig. 4A).