Laughlin M H, Simpson T, Sexton W L, Brown O R, Smith J K, Korthuis R J
Department of Veterinary Biomedical Sciences, University of Missouri, Columbia 65211.
J Appl Physiol (1985). 1990 Jun;68(6):2337-43. doi: 10.1152/jappl.1990.68.6.2337.
The purposes of this study were to determine whether exercise training induces increases in skeletal muscle antioxidant enzymes and to further characterize the relationship between oxidative capacity and antioxidant enzyme levels in skeletal muscle. Male Sprague-Dawley rats were exercise trained (ET) on a treadmill 2 h/day at 32 m/min (8% incline) 5 days/wk or were cage confined (sedentary control, S) for 12 wk. In both S and ET rats, catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX) activities were directly correlated with the percentages of oxidative fibers in the six skeletal muscle samples studied. Muscles of ET rats had increased oxidative capacity and increased GPX activity compared with the same muscles of S rats. However, SOD activities were not different between ET and S rats, but CAT activities were lower in skeletal muscles of ET rats than in S rats. Exposure to 60 min of ischemia and 60 min of reperfusion (I/R) resulted in decreased GPX and increased CAT activities but had little or no effect on SOD activities in muscles from both S and ET rats. The I/R-induced increase in CAT activity was greater in muscles of ET than in muscles of S rats. Xanthine oxidase (XO), xanthine dehydrogenase (XD), and XO + XD activities after I/R were not related to muscle oxidative capacity and were similar in muscles of ET and S rats. It is concluded that although antioxidant enzyme activities are related to skeletal muscle oxidative capacity, the effects of exercise training on antioxidant enzymes in skeletal muscle cannot be predicted by measured changes in oxidative capacity.
本研究的目的是确定运动训练是否会诱导骨骼肌抗氧化酶增加，并进一步阐明骨骼肌氧化能力与抗氧化酶水平之间的关系。将雄性Sprague-Dawley大鼠分为两组，一组进行运动训练（ET），每天在跑步机上以32米/分钟（8%坡度）跑2小时，每周5天，持续12周；另一组关在笼中（久坐对照组，S）。在S组和ET组大鼠中，所研究的六个骨骼肌样本中的过氧化氢酶（CAT）、超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GPX）活性与氧化纤维百分比直接相关。与S组大鼠的相同肌肉相比，ET组大鼠的肌肉氧化能力增强，GPX活性增加。然而，ET组和S组大鼠的SOD活性没有差异，但ET组大鼠骨骼肌中的CAT活性低于S组大鼠。暴露于60分钟缺血和60分钟再灌注（I/R）后，S组和ET组大鼠肌肉中的GPX活性降低，CAT活性增加，但对SOD活性几乎没有影响。I/R诱导的CAT活性增加在ET组大鼠的肌肉中比在S组大鼠的肌肉中更大。I/R后的黄嘌呤氧化酶（XO）、黄嘌呤脱氢酶（XD）和XO+XD活性与肌肉氧化能力无关，在ET组和S组大鼠的肌肉中相似。得出的结论是，尽管抗氧化酶活性与骨骼肌氧化能力相关，但运动训练对骨骼肌抗氧化酶的影响不能通过氧化能力的测量变化来预测。
