Bua Entela A, McKiernan Susan H, Wanagat Jonathan, McKenzie Debbie, Aiken Judd M
Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison, Wisconsin 53706, USA.
J Appl Physiol (1985). 2002 Jun;92(6):2617-24. doi: 10.1152/japplphysiol.01102.2001.
The hypothesis that the accumulation of electron transport system (ETS) abnormalities and sarcopenia are linked was investigated. Vastus lateralis, soleus, and adductor longus muscles were studied in 5-, 18-, and 36-mo-old male Fischer 344 x Brown Norway F(1) hybrid rats. A significant decrease in soleus and vastus lateralis muscle mass was observed with age. Adductor longus was resistant to muscle mass loss. Multiple serial sections were analyzed for the activities of cytochrome-c oxidase (COX) and succinate dehydrogenase (SDH). The number of fibers exhibiting a COX(-)/SDH(++) phenotype increased with age in both vastus lateralis and soleus muscles. No ETS-abnormal fibers were identified in adductor longus at any age. Cross-sectional area of ETS-abnormal fibers decreased in the abnormal region (region displaying COX(-)/SDH(++) phenotype), whereas control fibers did not. The vastus lateralis muscle, which undergoes a high degree of sarcopenia, exhibited more ETS abnormalities and associated fiber loss than the soleus and adductor longus muscles, which are more resistant to sarcopenia, suggesting a direct association between ETS abnormalities and fiber loss.
研究了电子传递系统（ETS）异常积累与肌肉减少症之间存在关联的假说。对5个月、18个月和36个月大的雄性Fischer 344×Brown Norway F(1)杂交大鼠的股外侧肌、比目鱼肌和长收肌进行了研究。随着年龄的增长，观察到比目鱼肌和股外侧肌的肌肉质量显著下降。长收肌对肌肉质量损失具有抗性。对多个连续切片分析了细胞色素c氧化酶（COX）和琥珀酸脱氢酶（SDH）的活性。在股外侧肌和比目鱼肌中，呈现COX(-)/SDH(++)表型的纤维数量随年龄增加。在任何年龄的长收肌中均未发现ETS异常纤维。ETS异常纤维的横截面积在异常区域（呈现COX(-)/SDH(++)表型的区域）减小，而对照纤维则没有。与比目鱼肌和长收肌相比，股外侧肌发生了高度的肌肉减少症，表现出更多的ETS异常和相关的纤维损失，比目鱼肌和长收肌对肌肉减少症更具抗性，这表明ETS异常与纤维损失之间存在直接关联。
