Ji L L, Fu R, Mitchell E W
Department of Kinesiology, University of Illinois, Urbana 61801.
J Appl Physiol (1985). 1992 Nov;73(5):1854-9. doi: 10.1152/jappl.1992.73.5.1854.
Glutathione status and antioxidant enzymes in various types of rat skeletal muscle were studied after an acute bout of exercise (Ex) at different intensities. Glutathione (GSH) and glutathione disulfide (GSSG) concentrations were the highest in soleus (SO) muscle, followed by those in deep (DVL) and then superficial (SVL) portions of vastus lateralis. In DVL, but not in SO or SVL, muscle GSH increased proportionally with Ex intensity and reached 1.8 +/- 0.08 mumol/g wet wt compared with 1.5 +/- 0.03 (P < 0.05) in resting controls (R). GSSG in DVL was increased from 0.10 +/- 0.01 mumol/g wet wt in R to 0.14 +/- 0.01 (P < 0.05) after Ex. Total glutathione (GSH + GSSG) contents in DVL were also significantly elevated with Ex, whereas GSH/GSSG ratio was unchanged. Activities of GSH peroxidase (GPX), GSSG reductase (GR), and catalase (CAT) were significantly higher in SO than in DVL and SVL, but there was no difference in superoxide dismutase activity between the three muscle types. Furthermore, Ex at moderate intensities elicited significant increases in GPX, GR, and CAT activities in DVL muscle. None of the antioxidant enzymes was affected by exercise in SO. It is concluded that rat DVL muscle is particularly vulnerable to exercise-induced free radical damage and that a disturbance of muscle GSH status is indicative of an oxidative stress.
在不同强度的急性运动（Ex）后，研究了大鼠不同类型骨骼肌中的谷胱甘肽状态和抗氧化酶。比目鱼肌（SO）中的谷胱甘肽（GSH）和谷胱甘肽二硫化物（GSSG）浓度最高，其次是股外侧肌深层（DVL），然后是浅层（SVL）。在DVL中，而非SO或SVL中，肌肉GSH随运动强度成比例增加，与静息对照组（R）中的1.5±0.03相比，达到1.8±0.08μmol/g湿重（P<0.05）。运动后，DVL中的GSSG从静息时的0.10±0.01μmol/g湿重增加到0.14±0.01（P<0.05）。DVL中的总谷胱甘肽（GSH+GSSG）含量也随运动显著升高，而GSH/GSSG比值不变。SO中的谷胱甘肽过氧化物酶（GPX）、谷胱甘肽二硫化物还原酶（GR）和过氧化氢酶（CAT）活性显著高于DVL和SVL，但三种肌肉类型之间的超氧化物歧化酶活性没有差异。此外，中等强度的运动使DVL肌肉中的GPX、GR和CAT活性显著增加。SO中的抗氧化酶均不受运动影响。结论是大鼠DVL肌肉特别容易受到运动诱导的自由基损伤，肌肉GSH状态的紊乱表明存在氧化应激。
