经皮电刺激防治失神经骨骼肌萎缩机制研究

The mechanism of treating denervated muscle atrophy with percutancous electric stimulation

目的研究电刺激对失神经骨骼肌萎缩中核因子-kB（nudear factor-kB，NF-kB）、肌肉环状指蛋白-1（muscleringfinger-1，MuRF1）表达变化的影响，探讨电刺激防治失神经骨骼肌萎缩的机制。方法选用Wista大鼠54只，制作成标准的右侧坐骨神经离断、腓肠肌失神经支配模型，随机分为对照组和电刺激组，应用RT-PCR和Western Bloting检测不同时段的NF-kB、MuRF1mRNA和蛋白质表达水平，联合肌湿重分析其相关性。结果失神经支配后腓肠肌NF-kB、MuRF1mRNA和蛋白质表达持续增加（P〈0．05）。电刺激组肌湿重比对照组同时间点明显增加（P〈0．05），NF-kB、MuRF1mRNA和蛋白质表达则明显降低（P〈0．05）。结论电刺激可以通过抑制NF-kB／MuRF1途径有效防治失神经骨骼肌萎缩。

Objective To investigate the effect of electric stimulation on changes of nuclear factor-kB （NF-kB） and muscle Ring Finger-1 （MuRF1） of denervated muscles, and explore the mechanism of muscle atrophy prevention by electric stimulation. Methods Gastrocnemius muscle denervation was created by transecting the right sciatic nerve in 54 Wister rats. The animals were then randomized to two groups, one with electric stimulation one without. Levels of NF-kB and MuRF1 mRNA and protein in the gastrocnemius muscle were detected by RT-PCR and western Blot at different intervals after denervation. The ratio of muscle wet weight was analyzed for comparison. Results The level of mRNA and protein of increased correspondingly at different intervals after denervation （ P 〈 0.05）. The group with electric stimulus had lower levels of NF-kB and MuRF1 of mRNA and protein, and higher muscle wet weight comparing to the denervation group. Conclusion Electric stimulation delays denervation muscle atrophy by inhibiting the NF-kB/MuRF1 pathways.