中文摘要：

目的观察长期中等强度有氧运动对小鼠心功能及心肌热休克蛋白表达的影响,初步探讨运动对小鼠心肌保护的可能机制。方法 16只昆明小鼠随机平均分为对照组和运动组。运动组小鼠给予中等强度跑步训练12周,对照组除不进行运动干预外,其余同运动组。运动干预前后,两组小鼠均采用心脏超声检测心脏结构和功能;运动干预后处死小鼠,取左室中部心肌行苏木精-伊红（HE）染色法观察心肌细胞的结构,另取左室上部心肌采用逆转录聚合酶链式反应（RT-PCR）方法观察心肌热休克蛋白（HSPs）信使RNA（m RNA）的表达,并运用Image-pro plus v 6.0图像分析软件对HSPs结果进行半定量分析。结果小鼠心脏超声显示,运动组小鼠心脏左室内径较对照组明显减小;心脏室间隔、左室后壁较对照组明显增厚;左室重量指数、射血分数较对照组明显增加。小鼠左心室游离壁光镜检查显示运动组小鼠心肌纤维排列有序,较对照组明显增粗,细胞体积明显增大,边缘变钝。RT-PCR结果显示运动组小鼠心肌HSP27、70、90和αβ-晶状体蛋白m RNA表达明显高于对照组。结论长期中等强度有氧运动可引起小鼠心肌肥厚,心功能增加。其机理可能与上调小鼠心肌HSPs m RNA表达有关。

英文摘要：

【Objective】To observe the effect of long-term moderate aerobic exercise on cardiac function and heat shock protein（HSP） expressions in mice, and discover the possible mechanism of protective effect of exercise on myocardium of mice.【Methods】Sixteen Kunming mice were randomly divided into two groups： the control group（n =8） and the exercise group（n =8）. The exercise group was forced to run with moderate intensity on a treadmill for 12 weeks. All the treatments in control group were the same as in the exercise group except no exercise involved. Cardiac structure and function of both groups were analyzed by echocardiography before and after the intervention. After the intervention, all the mice were sacrificed for HE staining and RT-？PCR analysis.【Results】The results of echocardiography showed that compared with the control group, the inner diameter of left ventricle was signifi cantly reduced, interventricular septum and left ventricular posterior wall thickness were both signifi cantly increased, left ventricular mass index and ejection fraction were also signifi cantly increased in the exercise group. Meanwhile, the HE staining showed that myocardium fi ber of the exercise mice arranged more orderly, cell volume increased, and the edge became blunt. Last, it was found that HSP 27, HSP70, HSP90, αβ- lensprotein m RNA expressions in exercise group were signifi cantly higher than those in control group.【Conclusion】Long-term moderate aerobic exercise can induce myocardial hypertrophy and a better heart function in mice. Increased HSPs expressions by exercise in mice myocardium might be one of the possible mechanisms.