有氧运动对心梗大鼠心肌组织Bax、Bcl-2、p53和TGF-β1表达及心功能的影响
Effects of Aerobic Exercise on the Expressions of Bax, Bcl-2, p53 and TGF-β1 and Cardiac Function in Myocardial Infarction Rats

摘要：目的：探讨有氧运动对心梗大鼠心肌Bax、Bcl-2、p53和TGF-β1表达及心功能的影响。方法：选取Sprague Dawley雄性大鼠34只，体重为180～220 g，随机抽取10只为假手术组（A组），其余24只大鼠行左冠脉前降支(LAD) 结扎术制作心梗(MI)模型，术后存活20只随机分为心梗组（B组）和心梗+有氧运动组（C组），每组10只，C组进行8周跑台有氧运动。训练结束后进行心功能测定和Masson染色观察，免疫组化检测心肌Bax、Bcl-2、p53和TGF-β1表达。结果：与A组比较，B组心系数显著下降（P＜0.01)，血流动力学指标LVSP和±dp /dtmax均显著下降（P＜0.01），LVEDP显著升高（P＜0.01），Bax、p53和TGF-β1的MOD值均显著升高，且p53和TGF-β1的MOD值升高极其显著（P＜0.01)；与B组比较，C组心系数显著提高（p＜0.05)、LVSP和±dp /dtmax均显著升高（P＜0.01），LVEDP显著降低（P＜0.01），心肌Bcl-2的MOD值显著升高（P＜0.01)，Bax、p53和TGF-β1的MOD值均降低，但p53显著降低（P＜0.01)。结论：大鼠MI后心肌组织Bax、p53和 TGF-β1的表达均显著升高，Bcl-2的表达降低，心肌细胞趋于凋亡；8周有氧运动可使MI大鼠心肌组织Bax、p53 和TGF-β1的表达显著降低，Bcl-2的表达显著升高，心肌细胞凋亡抑制，TGF-β1可能通过影响Bax和Bcl-2的表达参与了心肌细胞凋亡；有氧运动可能通过抑制MI大鼠细胞凋亡，减少心肌细胞丢失进而提高心脏功能。
Abstract: objective: The purpose of this study was to explore the effects of aerobic exercise on the expressions of Bax, Bcl-2, p53 and TGF-β1 and cardiac function in myocardial infarction (MI) rats. Methods: Thirty-four Sprague Dawley male rats, weighting about 180-220g, were selected. Ten of them were randomly selected for sham operation control group (group A), the other 24 rats were established MI model by ligaturing left anterior descending coronary artery (LAD), 20 of them were survival and were divided into myocardial infarction group (group B) and myocardial infarction + aerobic exercise group (group C). The group C rats were participated 8 weeks aerobic exercise. After training, the cardiac function was measured, and the expressions of Bax, Bcl-2, p53 and TGF-β1 were tested by Immunohistochemistry. Results: Compared with group A, the heart coefficient, LVSP and ±dp/dtmax in group B significantly decreased (P < 0.01), and the LVEDP, MOD of Bax, p53 and TGF-β1 in group B significantly increased (P < 0.05). Compared with group B, the heart coefficient, LVSP, ±dp/dtmax, and MOD of Bcl-2 in group C significantly increased (P < 0.05), the LVEDP, MOD of Bax, p53 and TGF-β1 decreased(P < 0.05). Conclusions: In MI rats, the expression of Bax, p53 and TGF-β1 increased, the expression of Bcl-2 decreased, and myocardial cell apoptosis increased. Eight weeks aerobic exercise could reduce the expressions of Bax, p53 and TGF-β1 in MI rats, increase rats’ Bcl-2, inhibit myocardial cell apoptosis; TGF-β1 may participate in the myocardial cell apoptosis by affecting the expression of Bax and Bcl-2. Aerobic exercise may improve heart function by inhibiting apoptosis to reduce myocardial cell loss in MI rats