有氧运动对线粒体质子跨膜转运及核糖核苷二磷酸还原酶的影响

本实验通过对有氧运动训练 (无负重游泳 6 0分钟 /天 ,7天 )大鼠游泳运动后的骨骼肌、心肌线粒体质子跨膜转运能力及核糖核苷二磷酸还原酶活性的测定 ,发现有氧运动训练的大鼠在定量运动负荷后 (6 0分钟无负重游泳 ) ,骨骼肌线粒体的质子跨膜转运能力显著提高 (P <0 0 5 ) ,以及线粒体的核糖核苷二磷酸还原酶活性明显高于对照组 (未经训练之大鼠 ,P <0 0 0 1)。而心肌线粒体的以上两项指标变化不甚明显。结果显示 ,骨骼肌线粒体对有氧运动训练的适应过程与其质子跨膜转运能力的提高及核糖核苷二磷酸还原酶活性增加有关。提示骨骼肌线粒体在慢性高氧化磷酸化状态刺激下 ,可能同时导致DNA生物合成的增加 ,即线粒体基因组对其功能变化产生应答反应。心肌线粒体的运动适应过程与骨骼肌线粒体不尽相同。

The Effect of Aerobic Exercise on the Proton-translocation across Mitochondrial Membrane and the Activity of Ribonucleotide Reductase

In our experiment, the ability of proton-translocation across mitochondrial membrane and the activity of ribonucleotide reductase were determined in skeletal muscle mitochondria and myocardial mitochondria in trained rat (60 min/day, 7 days) after unloading swimming for 60 min. The results showed that the ability of proton-translocation across mitochondrial membrane and activity of ribonucleotide reductase in skeletal muscle mitochondria were significantly increasing (P < 0.05, P < 0.001 respectively). The same items in myocardial mitochondria were no change. All these evidences suggested that the molecular adaptation of aerobic exercise in the skeletal muscle had been associated with proton-translocation across mitochondrial membrane and ribonucleotide reductase of mitochondria. The change of mitochondrial function may induce the response of mitochondrial DNA. The skeletal muscle mitochondria were more sensitive to aerobic exercise (redox stress) than the myocardial mitochondria in our experimental model.