递增负荷力竭性运动时大鼠血液氧化、抗氧化能力及RBCM生物物理特性的研究　

Study on Blood Oxidative, Antioxidative Capability and Biophysical Properties of Erythrocyte Membrane in Rats during and after Incremental Exercise to Exhaustion

利用自旋标记电子自旋共振（ＥＳＲ）技术，测定急性运动中及不同时程恢复期血浆抗坏血酸自由基（ＡＦＲ）和脂质过氧化水平（ＭＤＡ）的改变，同时观察红细胞膜（ＲＢＣＭ）脂流动性的变化。结果表明：血浆ＡＦＲ信号强度和ＭＤＡ水平在力竭运动后即刻均显著升高（均Ｐ＜０．００５），运动后３０ｍｉｎ仍维持高水平（均Ｐ＜０．０５），随后二者逐渐恢复，呈平行变化。ＲＢＣＭ脂尾部流动性在短时间中等强度运动（三级负荷末）即有明显下降（Ｐ＜０．０５），运动后恢复期进行性加重，并于运动后１２小时达非常显著改变（Ｐ＜０．０１）；此时膜脂头部流动性也明显下降（Ｐ＜０．０５），之后二者均有恢复趋势；提示递增负荷力竭性运动对ＲＢＣＭ脂流动性有重要影响，并且在运动诱导的氧化应激中，ＡＦＲ可作为一个有效的抗氧化指标，同时也反映了运动过程中及恢复期机体氧化、抗氧化系统的动态平衡。

The present study determined the changes of plasma ascorbate free radical(AFR), MDA level, and observed RBCM lipid fluidity during and after acute exercise by using electron spin resonance as well. The results showed that both the content of plasma MDA and the intensity of AFR signal increased to the highest level immediately after exercise (P＜0.005) and remained the high level 30 minutes post-exercise (P＜0.05). Then, they recovered gradually. The changes of MDA and AFR showed parallel. The tail fluidity of RBCM lipid decreased significantly during short time and middle-load intensity exercise. It deteriorated gradually and reached the lowest level 12 hours post exercise when the head fluidity of RBCM lipid began to decrease remarkably. Afterwards, both the tail and head fluidity tended to recover. The results suggested that incremental exercise to exhaustion had an important influence on RBCM lipid fluidity, and AFR was a valuable plasma antioxidant in exercise-induced oxidative stress. These data also suggested that during and after exercise, the oxidative and antioxidative system are in a status of a dynamic equilibrium.