脊髓电刺激对坐骨神经损伤大鼠背根神经节神经元和脊髓神经元的保护作用

目的 观察脊髓电刺激对大鼠坐骨神经切断后背根神经节(DRG)神经元和脊髓神经元的影响.方法 建立大鼠坐骨神经损伤模型,随机分为实验组(n=15)和对照组(n=15)；实验组行脊髓电刺激,对照组行假治疗.观察不同时期两组大鼠DRG神经元和脊髓神经元计数和超微结构；测定再生神经纤维髓鞘厚度及传导速度(NCV).结果 术后1、4、8周,实验组DRG神经元计数为15.74±1.47、14.17±1.20、13.33±0.47；对照组为10.99±1.38、10.33±0.78、9.20±0.56两者差异有统计学意义(P＜0.05).实验组脊髓神经元计数为17.16±0.50、15.86±1.27、11.55±0.95;对照组为12.16±0.92、10.27±0.44、9.24±0.78,两者差异有统计学意义(P＜0.05).结论 脊髓电刺激对周围神经损伤后DRG神经元和脊髓神经元具有保护作用.

Protective effect of epidural electrical stimulation on dorsal root ganglion and spinal cord motoneuron after sciatic nerve transection

Objective To observe the effect of epidural electrical stimulation on spinal cord motoneuron and dorsal root ganglion after sciatic nerve transection.Methods The model of sciatic nerve injury were established,and the rats were divided into 2 groups randomly.In the experimental group,the epidural stimulator was inserted into the correspond segments of spinal cord.In the control group,the same stimulator was inserted but no output current was given.The number of spinal cord motoneurons and dorsal root ganglion neurons was counted,and their ultrastructures were observed.The thickness of the myelin sheat of the regenerated nerve fiber and its conduction velocity at properly time were measured.Results At 1st,4th and 8th week after operation,the number of neurons of dorsal root ganglion in experimental group was 15.74 ± 1.47,14.17 ± 1.20 and 13.33 ±0.47,and that in control group was 10.99 ± 1.38,10.33 ±0.78 and 9.20 ±0.56 respectively.The number of neurons of anterior horn of spinal cord in experimental group was 17.16 ± 0.50,15.86 ± 1.27 and 11.55 ± 0.95,and that in control group was 12.16 ±0.92,10.27 ± 0.44 and 9.24 ± 0.78 respectively.Statistically,there was significant difference in the number of neurons between experimental group and control group (P ＜ 0.05 ).Conclusion Epidural pulse-electrical stimulation could prevent the apoptosis of perikaryon and protect the normal structures of the spinal cord motoneurons and dorsal root ganglions.