颈7神经根切断后靶肌肉运动终板的形态变化  

The morphological changes of motor end-plate in target muscles after C7 nerve root transection

作　　者：姜宗圆[1] 顾施辉[2] 徐雷[2] 徐建光[2] 顾玉东[2] 

机构地区：[1]皖南医学院附属弋矶山医院手外科,芜湖241000 [2]复旦大学附属华山医院手外科卫生部手功能重建重点实验室上海市周围神经显微外科重点实验室医学神经生物学国家重点实验室,上海

出　　处：《中华手外科杂志》2014年第1期5-9,共5页Chinese Journal of Hand Surgery

基　　金：上海市周围神经显微外科重点实验室课题项目（08DZ2270600）;卫生部国家临床重点专科建设项目（2010）

摘　　要：目的研究颈，神经根切断后主要靶肌肉内运动终板形态学的变化过程，探索颈7神经根切断术后的代偿机制。方法42只雄性sD大鼠，随机分成7组，每组6只。同一只大鼠右侧建成颈，神经根切断模型，左侧为对照组。用乙酰胆碱酯酶染色、银．乙酰胆碱酯酶染色、免疫荧光染色和电镜等技术手段检测术后第1、2、4、6、8、12周大鼠的肱三头肌、背阔肌和指总伸肌内运动终板形态学的变化过程。所有数据均用SPSS17．0软件进行均值、标准差计算和方差统计学分析。结果颈，神经根切断后1～3周，主要靶肌肉内运动终板的形态结构无明显变化。颈，神经根切断后4—8周，靶肌肉内某些区域出现少数面积明显增大，乙酰胆碱酯酶淡染，电镜下超微结构严重退变的运动终板。术后12周，运动终板结构得以恢复，并可能在老运动终板附近出现多个小的特化的突触后膜聚集区，以形成新的运动终板。结论颈，神经根切断后，靶肌肉内运动终板微观形态学会出现改变，并在术后12周基本恢复正常。而来源于邻近正常神经的轴突出芽可能是重要的颈，神经根切断术的代偿方式。Objective - To explore the compensatory mechanisms after severing the C7 nerve root by studying the morphological changes of motor end-plate in target muscles. Methods Forty-two male SD rats were randomly divided into 7 groups, with 6 each. （17 nerve root on the right side was transected while that on the left side was left intact. At 1, 2, 4, 6, 8, and 12 weeks after C7 nerve root transection, the triceps brachii, latissimus dorsi and extensor digitorum communis muscles of the experimental side and the normal side were harvested and subjected to acetylcholinesterase staining, silver-acetylcholinesterase staining, immunofluorescence staining and electron microscopy. The morphological changes of the motor end-plate in these muscles were recorded and analyzed. SPSS 17.0 software was used to calculate the mean, standard deviation and analysis of variance. Results Within 1 to 3 weeks of C7 transection, there were no significant morphological changes of the motor end-plate in target muscles. Between 4 to 8 weeks post transection, a small number of abnormal motor end-plates with features of larger area, lighter acetylcholinesterase staining and severe ultrastructural degeneration under electron microscopy emerged sparsely in some spots in the target muscles. The morphology of motor end- plate returned to normal status 12 weeks following C7 transection. Multiple small specialized postsynaptic membrane aggregations appeared in the neighborhood of the original nerve terminal to form new motor end-plates. Conclusion Morphological changes of the motor end-plate happened in target muscles after C7 nerve root transection. These changes returned to normal in 12 weeks. Axonal sprouting derived from adjacent healthy nerve fibers could be the main mechanism of compensation in C7 nerve transfer.

关 键 词：乙酰胆碱酯酶 显微镜检查 电子 免疫荧光抗体技术 颈7神经根 轴突出芽 

分 类 号：R651.3[医药卫生—外科学]