Inhibition of p38 MAPK by SB203580 pretreatment significantly improved myocardial infarct size (Figures 6(a)–6(b)), reduced serum cTnI level (Figure 6(c)), and alleviated [Ca2+]i overload (Figure 6(d)) during I/R-induced myocardial injury in rats. This evidence concerns the gene TNNI3 and myocardial infarction.