应用局部电刺激建立椎孔外颈神经卡压综合征动物模型的实验研究

Establishment of animal model of extra vertebral foramen cervical nerve entrapment syndrome by local electrical stimulation-an in vivo experimental study

目的探讨局部电刺激致椎孔外颈神经卡压的可能性，为今后进一步开展各项研究奠定基础。方法研制微型电脉冲神经肌肉刺激器，设定合适的刺激参数。经预处理后植入成年SD大鼠体内，予以每天8h间歇电刺激。对照组大鼠20只包括10只假手术组和10只植入导线组，剩余40只进入实验组，同时行自身对侧对照。假手术组不植入刺激器；植入导线组在相同区域同样植入包有硅胶套管的电极导线。于植入后的2、3、4、5周观察各组动物行为改变。行电生理检测后，处死动物取材分别于光镜及电镜下行各项组织形态学检测，结果进行统计学分析。结果刺激器植入2周后，实验组动物实验侧颈肩部及上肢肌肉即可测得正尖、纤颤等失神经电位改变，变化程度随植入时间增加而增大。光镜检测与对照组相比，实验组3周后，肌纤维轻度萎缩；4周后，肌纤维退行性改变；5周后，局部可见纤维化改变及软骨细胞化生，神经纤维周围也可见炎症反应及纤维化改变。且实验组动物局部肌肉与对照组相比明显萎缩（P〈0．05）。电镜检测示髓鞘变性，炎性细胞浸润。结论局部电刺激的方法可用于建立椎孔外颈神经卡压综合征的动物模型。颈神经后支卡压可能是椎孔外卡压综合征产生的启动因素。

Objective To discuss the possibility of establishing animal model of extra vertebral foramen cervical nerve entrapment syndrome by local electrical stimulation, which can build foundation for further study. Methods Make miniature electric stimulation equipment, setting suitable parameter, which was implanted into body of SD rats, after pretreatment. Put 8 hours intermittent stimulation on them. Control group includes sham operation one and guideline implanted one. After 2, 3, 4 and 5 weeks. Observe the behavior of animal and detect electrophysiological signal. Then execute the animal and conduct various histolo- gy and morphology detection via light microscope and electron microscope respectively. Statistic analysis was done to evaluate the results. Results Denervation potential was observed after stimulation. Just 2 weeks later, positive sharp potential and ventricular fibrillation potential in neck-shoulder region of experimental group were detected. Morphological change includes myelin sheath degeneration and inflammatory cell invasion. 3 weeks later, there was slight atrophy in muscle fibre; 4 weeks, there was retrogression change; 5 weeks, there was fibrosis and cartilage cell metaplasia and also inflammation reaction and fibrosis around the nerve fiber. Local muscle area of cross section , which were 3433.92±298.89 （3w）, 2396.31±591.43（4w） and 1185.72±337.92 （5w） were smaller than that of control group （5554.45±412.28） after electrical stimulation, （P〈 0.05）.Conclusion local electric stimulation can be used to establish the animal model of extra vertebral foramen cervical nerve entrapment syndrome. Compression of cervical dorsal rami maybe the startup factor of extra vertebral foramen cervical nerve entrapment syndrome.