不同速度运动后大鼠骨骼肌氧化还原状态的变化及乳酸阈的形成

Redox State Changes and Lactate Threshold in Rat Skeletal Muscle After Running at Different Speeds

本研究的目的在于观察不同速度运动后大鼠骨骼肌氧化还原状态的变化及其与乳酸阈形成之间的关系。通过测定不同速度运动后 SD 大鼠骨骼机 NADH 和 NAD 含量变化发现,低强度运动后 NADH下降,中等强度运动后又升高,肌乳酸均有少量增加。在乳酸阈速度时,NADH 含量和 NADH/NAD 比值呈现出迅速增加的趋势。由此得出结论:中等强度运动后 NADH 含量升高主要是线粒体内 NADH 发生改变;肌肉 NADH/NAD 比值的变化对乳酸阈的形成是极其重要的调节因素。在中强度时细胞即开始向还原状态转变,可能对加速乳酸的积累和乳酸阈的形成具重要意义。

The purpose of this study was to investigate the redox state changes in rat skeletal muscle after running at differentspeeds and the relationship between muscle redox state and the lactate threshold.Muscle NADH,NAD and lactate contentwere determined after the SD rat ran at different speeds.The results showed that the NADH level dropped after running atlow speed and then rose as the speed increased to intermediate level,while lactate concentration showed a slight increase allthrough.It is concluded that the increase in muscle NADH content mainly resulted from the changes of the mitochondrial NADH after running at intermediate speed.The changes in the muscle NADH/NAD ratio constitue a very important regula-tive factor for the formation of the lactate threshold.The fact that the cells began to transform into the redox state may beof significance to speeding lactate accumulation towards threshold formation.