甲钴胺对大鼠受损背根节A-类神经元自发放电的抑制作用  

Inhibitory effects of methylcobalamin on the spontaneous discharges of chronically compressed A-type dorsal root ganglion neurons of rats

作　　者：张明[1] 韩文娟[1] 胡三觉[1] 徐晖[1] 

机构地区：[1]第四军医大学神经科学研究所,西安710032

出　　处：《神经解剖学杂志》2013年第3期259-264,共6页Chinese Journal of Neuroanatomy

基　　金：国家自然科学基金(30870830);教育部留学回国启动基金(HG3503)

摘　　要：目的:研究甲钴胺(methylcobalamin,Methyl B12)对损伤背根节(dorsal root ganglion,DRG)A-类神经元的不同模式自发放电的作用。方法:在大鼠L5椎间孔植入不锈钢柱制备大鼠DRG慢性压迫模型(chronic com-pression of DRG,CCD)上,利用在体单纤维细胞外记录方法研究Methyl B12对受损DRG神经元自发放电的影响。结果:(1)CCD模型大鼠出现明显的双侧机械刺激引起缩足反应阈值降低(P<0.001);(2)Methyl B12(300μmol/L)对受损A-类DRG神经元自发放电具有显著的抑制作用(n=13,P<0.05);(3)Methyl B12(300μmol/L)对受损A-类DRG神经元非周期和周期放电模式自发放电均有抑制作用,且两者之间没有明显差异。结论:Methyl B12(300μmol/L)对受损DRG A-类神经元产生的异位自发放电具有抑制作用,且对于非周期和周期放电模式的抑制作用没有差异。Objective： To explore the effects of methylcobalamin （Methyl B12） on the spontaneous discharges of A-type neuron with different firing patterns in the injured dorsal root ganglion （DRG） . Methods： The extracellular single fiber recording technique in vivo was applied on the chronic compression of DRG （CCD） models which was made by inserting a piece of stainless rod into the ipsilateral L5 intervertebral foramen of rats and recorded the the effects of Methyl B12 on the spontaneous discharges of the injured DRG neurons. Results ： （ 1 ） The bilateral mechanical paw withdrawal thresholds were significantly decreased after CCD in the experimental and control group （ P 〈 0. 001 ） ; （ 2 ） Spontaneous discharges of A-type DRG neurons were obviously inhibited by Methyl B12 （300 μmol/L, n = 13, P 〈 0.05） ; （3） The discharge frequency of non-periodic and periodic discharge pattern were both depressed by Methyl B12 （300 μmol/L） , but there was no significant difference between them. Conclusion： The spontaneous discharges of chronic compressed DRG A-type neurons were greatly inhibited by Methyl B12 （300 μmol/L）. And there was no significant difference of inhibition induced by Methyl B12 between non-periodic and periodic discharge patterns.

关 键 词：甲钴胺 背根节 自发放电 神经病理性疼痛 大鼠 

分 类 号：R338[医药卫生—人体生理学]