【摘要】 背景:骨骼肌细胞凋亡会导致多种骨骼肌疾病的出现,常规疗法效果都不太理想。目的:分析不同强度运动对大鼠骨骼肌形态结构和细胞凋亡的影响,可以起到预防骨骼肌细胞凋亡的作用。方法:健康3月龄雄性SD大鼠30只随机分为3组:安静对照组、一般有氧运动组和长时间大强度运动组。安静对照组不进行游泳运动,运动组运用游泳运动制备动物模型,运动组的训练周期都为10周,10周后对大鼠全部实施麻醉后取腓肠肌,用以苏木精-伊红染色观察骨骼肌形态和TUNEL检测细胞凋亡情况;并检测骨骼肌组织超氧化物歧化酶、丙二醛含量,做丙二醛与积分吸光度的相关分析。结果与结论:(1)骨骼肌苏木精-伊红染色结果:长时间大强度运动组肌纤维排列紊乱、结构模糊;(2)丙二醛和超氧化物歧化酶含量:与安静对照组相比,一般有氧运动组、长时间大强度运动组的丙二醛增加,一般有氧运动组与安静对照组相比较超氧化物歧化酶有显著性增加(P<0.05),长时间大强度运动组与有氧组相比较超氧化物歧化酶显著性减少(P<0.05);(3)TUNEL检测结果:长时间大强度运动组细胞凋亡积分吸光度值显著高于一般有氧运动组和安静对照组(P<0.01);(4)相关分析:丙二醛与积分吸光度值之间显著相关,呈正相关关系;(5)结果说明,长时间大强度运动组骨骼肌组织中的长丙二醛增多,机体疲劳程度更为严重。有氧运动使机体骨骼肌逐渐有适应性,而由于过度运动负荷较大,对骨骼肌形态结构有一定损伤,使得细胞凋亡增加。随着运动强度增加导致丙二醛生成增加而清除相对不足,细胞凋亡积分吸光度值增大。更多还原

【Abstract】 BACKGROUND: Apoptosis in the skeletal muscle leads to a variety of skeletal muscle diseases, but there are ideal no therapies so far. OBJECTIVE: To analyze the effects of different intensities of exercises on the morphology and apoptosis of the skeletal muscle in rats. METHODS: Thirty healthy male 3-month-old Sprague-Dawley rats were randomly allocated into three groups(n=10 per group): control group(no swimming), aerobic exercise and high-intensity exercise groups. The rats in the exercise groups underwent swimming for consecutive 10 weeks. Then, the gastrocnemius muscle was isolated from all rats under anesthesia. The morphology and cell apoptosis were detected by hematoxylin-eosin staining and TUNEL test. At the same time, the levels of superoxide dismutase and malondialdehyde in skeletal muscle tissue were tested and the correlation of malondialdehyde with integrated optical density(IOD) was analyzed. RESULTS AND CONCLUSION: The results of hematoxylin-eosin staining showed that the muscle fibers were in disorder arrangement with obscure structure in the high-intensity exercise group. Compared with the control group, the content of malondialdehyde was increased in the exercise groups, especially in the aerobic exercise group(P < 0.05). The level of superoxide dismutase in the high-intensity exercise group was significantly lower than that in the aerobic exercise group(P < 0.05). The results of TUNEL test showed that the IOD values in the high-intensity exercise group were significantly higher than those in the aerobic exercise and control groups(P < 0.05). There was a positive correlation of malondialdehyde with IOD. These results indicate that the long-term and high-intensity exercise can increase the content of malondialdehyde in the skeletal muscle, resulting in an aggravation of fatigue. Aerobic exercise can obtain the adaptation of the skeletal muscle, but damage the morphology and structure of the skeletal muscle because of excessive exercise load, thus accelarating the cell apoptosis. With the exercise intensity increasing, the balance between malondialdehyde production and clearance is broken, and the IOD value is increased.更多还原