坐骨神经挤压伤小鼠神经肌肉接头与肌梭的失神经和神经再支配的形态学研究  

A morphological study of denervation and reinnervation of neuromuscular junction and muscle spindle after sciatic nerve crush in mice

作　　者：李强[1] 蓝永生[2] 王江波 李月影[1] 李剑南 崔树森[1] 曹让娟[1] LI Qiang;LAN Yongsheng;WANG Jiangbo;LI Yueying;LI Jiannan;GUI Shusen;CAO Rangjuwi(Department of Hand Surgery,China-Japan Union Hospital,Jilin University,Changchun 130033,China;Changchun Normal University,Changchun 130032,China)

机构地区：[1]吉林大学中日联谊医院手外科,长春130033 [2]长春师范大学,长春130032

出　　处：《中华显微外科杂志》2021年第4期408-413,共6页Chinese Journal of Microsurgery

基　　金：吉林省自然科学基金(20200201489JC);吉林大学优秀青年教师培养计划(重点培养项目)。

摘　　要：目的观察小鼠坐骨神经挤压伤模型中靶肌肉内神经肌肉接头(NMJ)与肌梭在神经损伤后及再生中的失神经、神经再支配的变化过程。方法2019年1月至2019年10月,18只C57BL/6小鼠随机分为坐骨神经挤压伤组(损伤组,12只)和对照组(假手术组,6只)。损伤组分别在损伤后1、2、3 d及4周取材,对照组于损伤后3 d及4周后取材,均取手术侧胫前肌,行神经纤维丝抗体(NF)、突触素抗体(Syn)以及荧光偶联的银环毒素(α-BTX)免疫荧光组织化学染色。所得数据使用非配对t检验进行数据分析,P<0.05为差异有统计学意义。结果坐骨神经损伤3 d后,损伤组中完全失神经支配的神经肌肉接头比例为(92.40±8.85)%,与对照组(5.19±1.32)%相比差异有统计学意义(P<0.05);损伤2 d后,损伤组的肌梭中两端的γ-运动神经成分即消失,位于其中部的感觉神经螺旋缠绕结构于伤后3 d消失。损伤4周后,对照组与损伤组在神经肌肉接头的神经支配情况相比,未获神经支配[分别为(3.02±0.78)%和(4.22±2.08)%]、部分获神经支配[分别为(6.44±1.91)%和(7.94±2.12)%]以及完全神经支配[分别为(90.54±10.44)%和(87.84±13.89)%]两组之间差异均无统计学意义(P>0.05)。损伤后4周时,损伤组中肌梭的神经再支配不佳,两端的乙酰胆碱受体已有神经支配,但不完全;肌梭中部神经纤细、不连续且无典型的螺旋缠绕结构。结论坐骨神经损伤后,NMJ和肌梭失神经速度相当;肌梭的运动神经先于感觉神经发生变性。神经肌肉接头易于被再生的神经支配,但肌梭的神经再支配较为困难,其中,肌梭的运动神经较感觉神经容易恢复神经再支配。Objective To observe the denervation and reinnervation of the neuromuscular junction(NMJ)and muscle spindle after sciatic nerve crush in mice.Methods From January,2019 to October,2019,18 C57BL/6 mice were randomly and evenly divided into injured groups(sciatic nerve crush group,12 mice)and control groups(sham group,6 mice).Mice in the injured group were sacrificed at day-1,day-2,day-3 and 4 weeks after the sciatic nerve injury.Mice in the control group were sacrificed at day-3 and 4 weeks from the day of experiment.The tibialis anterior muscles with crushed nerve were collected for immunohistochemistry staining by neurofilament(NF),synapto-physin(Syn)and a-bungarotoxin(a-BTX).Data were analysed by unpaired t-test.P<0.05 was considered significant difference.Results The completely denervation of NMJ reached(92.4±8.85)%at day-3 after the nerve crush,compared with(5.19±1.32)%in the control group(P<0.05).However,the muscle spindle lostγ-motor neuron innervation at day-2 after the nerve crush and completely denervated at day-3 after the surgery.For the reinnervation,no difference of no reinnervation of NMJ[(3.02±0.78)%vs.(4.22±2.08)%],partial reinnervation of NMJ[(6.44±1.91)%vs.(7.94±2.12)%]and completely reinnervation of NMJ[(90.54±10.44)%vs.(87.84±13.89)%]were observed between the control group and the injured group 4 weeks after,the injury.While,for the muscle spindle,only the acetylcholine receptors at each end were partly reinnervated.The innervation of the middle part of the muscle spindle was thin and discontinued without typical spiral winding structure.Conclusion The denervation speed of NMJ and muscle spindle was comparable after the peripheral nerve injury.The 7-motor neuron lost innervation ahead of the sensory neuron in the muscle spindle.The reinnervation of NMJ is earlier than that of the muscle spindle,and the re-innervation of the y-motor neuron is prior to the sensory neuron in the muscle spindle.

关 键 词：坐骨神经损伤 神经肌肉接头 肌梭 失神经支配 神经再支配 小鼠 

分 类 号：R745[医药卫生—神经病学与精神病学]