RESUMO
<p><b>OBJECTIVE</b>To observe the dynamic expression changes of p38 mitogen-activated protein kinase (p38MAPK), nucler facter kappa B (NF-κB) and cyclooxygenase-2 (COX-2) in myocardial tissue after an exhausted exercise and study the impact of p38MAPK, NF-κB and COX-2 on its myocardial damage.</p><p><b>METHODS</b>Sixty Wister male rats were randomly divided into the control group (n = 10) and the exhausted exercise group (n = 50). Then the exhausted exercise group was further divided into 5 subgroups, namely 0 h, 3 h, 6 h, 12 h, 24 h after an exhausted exercise (n = 10). The myocardial injury animal model was set up by using an exhausted swimming exercise and the expression of p-p38MAPK, NF-κB and COX-2 were examined by Western blot.</p><p><b>RESULTS</b>Compared with the control group, the expression of p-p38MAPK were increased significantly (P < 0.01) in all the groups and the 3 h group was the highest( P < 0.01); The expression of NF-κB were increased significantly (P < 0.05) in all the groups but 0 h P > 0.05) and the 6h group was increased significantly compared with the other groups( P < 0.05); The expression of COX-2 were increased significantly( P < 0.05) in all the groups but 0 h and the 24 h groups was increased significantly compared with the other groups(P < 0.05).</p><p><b>CONCLUSION</b>p38MAPK was activated in an acute exhausted exercise, p-p38MAPK may play an important role in modulating NF-κB and COX-2 expression and mediating the exhausted exercise induced myocardial damage.</p>