Myosin specific-T lymphocytes might mediate myocardial inflammation and remodeling after AMI. Myosin-activated or unactivated T lymphocytes in vitro were transferred into naive syngeneic rats, respectively. T lymphocyte infiltration and myocyte apoptosis were explored by the HE and TUNNEL. Proteins and mRNA levels of cytokines (IL-1beta, IL-6 and TNF-alpha) in myocardium were determined by RT-PCR and immunohisto-chemistry. T lymphocyte infiltration was evidently observed after one week of activated T cell transfer. The expressions of cytokines were elevated markedly one week later. The myocyte apoptosis occurred after T lymphocyte infiltration in myocardium. Our findings suggest that cardiac myosin activated-T lymphocytes may mediate myocardial inflammation and remodeling.