观察大负荷运动后不同时间点骨骼肌线粒体融合与分裂蛋白的变化,分析与探究线粒体融合与分裂之间的关系及其生理意义。方法:56只SD大鼠经适应后分安静对照组(8只)和运动组(48只),运动模型为一次中大强度离心跑台运动,-16°,20m/min,90min。运动大鼠分别在运动后即刻、6h、12h、24h、48h和72h(各时间点8只)取比目鱼肌。Western blotting方法分析骨骼肌Mfn1、Mfn2、Opa1、Fis1和Drp1的蛋白表达。结果:Mfn1蛋白在运动后即刻表达升高,而后降低,72h为最低点;Mfn2蛋白在运动后呈先降后升的变化趋势;Opa1蛋白在运动后表达先降低后升高,24h为最高点,而后逐渐降低;Drp1蛋白在运动后表达升高,6h出现高峰,而后逐渐降低;Fis1蛋白在运动后表达升高,12h为最高点,而后在48h和72h表达降低。结论:一次大负荷运动后大鼠骨骼肌线粒体融合、分裂失衡,主要表现为线粒体分裂增强、线粒体融合抑制;而在运动恢复期,骨骼肌线粒体融合、分裂之间重塑平衡状态。
The purpose of this study was to investigate the changes of mitochondrial fusion and fission in skeletal muscle induced by high-load exercise,and to analyze the relations of mitochondrial fusion and fission.Methods:56SD rats were divided into two groups:control group(8)and exercise group(48).The rats should run on the treadmill,16°,20m/min,90 minutes.The soleus were taken after exercise immediately,6hours,12 hours,24hours,48 hours and 72 hours from the rats in exercise groups.WB was used to detect the protein expressions of Mfn1,Mfn2,Opa1,Fis1 and Drp1.Results:The expression of Mfn1 protein increased after the exercise,and then decreased gradually.And the lowest appeared at 72-hour after the exercise.There were not remarkable changes of the expression of Mfn2 protein.The expression of Opa1 protein decreased after the exercise,and then increased gradually.And the highest appeared at 24-hour after the exercise.The expression of Fis1 protein increased after the exercise,and the peak was at12-hour.But the expressions decreased at 48-hour and 72-hour after the exercise.Conclusion:A bout of high-load exercise leads to imbalanced mitochondrial fission and fusion in skeletal muscle,shown by the enhanced mitochondrial fission and the declined mitochondrial fusion.And the balance of mitochondrial fusion and fission rebuilds after the exercise.