Myostatin在小鼠腓肠肌失神经支配萎缩过程中的表达

目的:分析myostatin在腓肠肌失神经支配萎缩过程中的表达变化及其在肌萎缩过程中的作用。方法:采用坐骨神经横断术制备小鼠腓肠肌失神经支配模型,实时荧光定量PCR和Western印迹法分别检测失神经支配不同时段腓肠肌myostatin mRNA和蛋白表达水平,并对失神经前后肌肉湿重比、肌纤维横截面积进行比较。结果:失神经支配1 d时,腓肠肌myostatin mRNA迅速上升,3 d达到高峰,随后逐渐下降,而相应蛋白水平逐渐增高,7 d达到高峰继而逐渐下降,至56 d时mRNA和蛋白水平仍略高于正常水平。结论:腓肠肌失神经支配萎缩过程中myostatin的表达变化是一重要的分子事件。

Expression of myostatin in atrophic gastrocnemius of mouse after denervation

Objective: To investigate the expression of myostatin and explore its potential role in atrophic gastrocnemius after denervation.Methods: The mouse model of sciatic nerve resection was prepared to examine the levels of myostatin mRNA and protein expression in the atrophying mouse gastrocnemius muscle at different time points after denervation by realtime quantitative RT-PCR and Western blot,respectively.In parallel,morphometric analyses of the atrophying muscle including measurements of the wet weight ratio of the muscle and the cross section area (CSA) of the muscle fibers were also conducted.Results: The level of myostatin mRNA in gastrocnemius increased instantly at day 1 after denervation,reached the peak value at day 3 after denervation,followed by a subsequent decrease;while the level of myostatin protein increased continuously after denervation,reached a peak at day 7 after denervation,and then decreased gradually until day 56 after denervation.But the level of both myostatin mRNA and protein at day 56 after denervation was still higher than the normal level.The significant decrease of the muscle wet weight ratio and CSA were also observed.Conclusion: Myostatin might play an important role in the process of mouse gastrocnemius atrophy after denervation.