中文摘要：

目的：观察一次大负荷离心运动后线粒体的分布以及线粒体SDHA和Cyt C蛋白的表达变化。方法：42只SD大鼠经适应后随机分为安静组（6只）和一次大负荷离心运动组（36只）。运动组在跑台上进行90 min速度为16 m/min的离心运动,坡度-16°。运动后分别在0、6、12、24、48、72 h取材。透射电镜观察大鼠骨骼肌线粒体分布,western blotting测定骨骼肌线粒体SDHA和Cyt C蛋白的表达。结果：一次大负荷离心运动后,骨骼肌肌膜下线粒体面积和数量均升高,肌原纤维间线粒体面积和数量呈现减少趋势;与安静组相比,肌膜下线粒体面积增加明显;骨骼肌线粒体SDHA蛋白表达呈现先降低后升高的趋势,而Cyt C蛋白呈现升高趋势。结论：一次大负荷离心运动后骨骼肌线粒体分布出现肌膜下聚集现象,且线粒体SDHA蛋白表达在运动后下调明显,可能是导致线粒体功能下降的原因之一。

英文摘要：

Objective： The purpose of this study was to observe the effect of a heavy load eccentric exercise on mitochondria distribution and SDHA,Cyt C protein expressions. Methods： Forty-two SD rats are randomly divided into rest group（ 6 rats） and a heavy load eccentric exercise group（ 36 rats）. Exercise group rats ran on treadmill at the speed of 16 m / min with-16°,90 min in total. Muscle samples were taken immediately,6 h,12 h,24 h,48 h and 72 h after exercise. Mitochondria distribution was observed by TEM,and the protein expressions of SDHA and Cyt C were tested by Western blotting. Results： The mitochondrial number and area under skeletal muscle membrane increased after exercise,and those between myofibrils showed a decreasing trend. Compared with rest group,the mitochondrial area under muscle membrane increased,the protein expression of SDHA increased first and then decreased while the protein expression of Cyt C increased. Conclusions： Mitochondria distribution under the muscle membrane was gathered after a heavy load eccentric exercise; the SDHA protein expression in mitochondria decreased after exercise,which may be one of the reasons resulting in the decline of mitochondrial function.