慢性压迫性脊髓损伤后周围神经退变与MAP1B表达变化的实验研究  

Degeneration of peripheral nerves and expression changes of microtubule-associated protein 1B in rats after chronic spinal cord compression

作　　者：李利军[1] 宋洁富[1] 魏杰[1] 常峰[1] 苏云星[1] 常保国[1] 

机构地区：[1]山西省人民医院骨科,太原030001

出　　处：《中华神经医学杂志》2011年第10期984-988,共5页Chinese Journal of Neuromedicine

摘　　要：目的观察慢性压迫性脊髓损伤大鼠运动功能、周围神经形态学改变及微管相关蛋白1B（MAP1B）的表达变化情况。方法50只Wistar雌性大鼠按照随机数字表法分为正常组、假手术组、慢性压迫20％组、慢性压迫40％组、慢性压迫60％组，每组10只。后3组置入平头塑料螺钉对大鼠脊髓进行后路渐进性压迫，2个月后分别压迫到20％、40％、60％左右程度。正常组不做任何处理，假手术组只做k棘突和部分椎板咬除术，不实施压迫。造模后60d处死大鼠取坐骨神经作为标本，行HE染色，于光镜及电镜下观察，同时行MAP1B的免疫组化染色。结果各压迫组大鼠运动功能减退；Tarlov评分、斜板实验评分、BBB-21评分均明显低于正常组大鼠，差异有统计学意义（P〈0．05）。各压迫组大鼠均出现明显的周围神经退变现象，并且压迫程度越重变化越显著。各压迫组周围神经轴突中MAP1B的表达均降低，与正常组比较差异有统计学意义（P〈0．05）。结论脊髓损伤后周围神经发生退变，且因为神经元凋亡、坏死或受抑制使得轴突的再生不明显，造成脊髓损伤后功能恢复不良。Objective To observe the morphological changes of the peripheral nerves, the expression changes of microtubule-associated protein 1B （MAP 1 B） and the changes of motor function in rats after chronic spinal cord compression. Methods A total of 50 female Wistar rats were randomly divided into normal control group （n=10）, sham-operated group （n=10） and chronic compressive groups （n=30）. The rats in the chronic compressive groups were given gradual compression on the posterior spinal cord using blunt plastics screw; compression degree reached 20% （n=10）, 40% （n=10） and 60% （n=10）, respectively, after 2 months. Rats in the normal control group did not receive any treatment and rats in the sham-operated group was only given removal of the L5 spinous process and part of the vertebral plate. Following sacrifice of the rats, cells from sciatic nerves were removed for HE staining; light microscopy and electron microscopy were employed to observe the changes; immunohistochemical staining of MAP1B was performed. Results Hypokinesia, and decreased Tarlov scores, Ramp test scores and BBB-21 scores in the chronic compressive groups were noted as compared with those in the normal control group （P〈0.05）. Peripheral nerve degeneration was noted in all the chronic compressive groups; the more severe the compression, the more significant the degeneration. Expression of MAP1B in the peripheral nerves of the chronic compressive groups was significantly down-regulated as compared with that in the normal control group （P〈0.05）. Conclusion Spinal cord compressive injury can lead to peripheral nerve degeneration; and neuronal apoptosis and necrosis lead to rare axonal regeneration, which may be one of the important reasons that influences the neural function recovery after chronic spinal cord compression.

关 键 词：脊髓损伤 周围神经 微管相关蛋白 神经退变 轴突再生 

分 类 号：R651.2[医药卫生—外科学]