坐骨神经冷损伤后的病理改变与基因表达谱研究  

Pathology and gene expression of the sciatic nerve after non-freezing cold injury

作　　者：徐敏[1] 耿志伟[1] 宋珏娴[1] 李浩[1] 吴忧[1] 刘芳艳[1] 刘璐[1] 贾建平[1] 

机构地区：[1]首都医科大学宣武医院神经内科,北京100053

出　　处：《中华物理医学与康复杂志》2010年第8期578-583,共6页Chinese Journal of Physical Medicine and Rehabilitation

摘　　要：目的 通过观察大鼠坐骨神经在非冻结性冷损伤后,坐骨神经以及L4、L5、L6背根神经节（DRG）感觉神经元的形态学变化以及mRNA转录谱的变化,初步探讨周围神经冷损伤及修复的分子机制.方法 24只雄性Wistar大鼠分为实验组和对照组,每组12只,实验组右侧坐骨神经冷损伤（4℃,2 h）,对照组左侧坐骨神经同样方法暴露,但不给予冷处理.分别于冷损伤后1,2,3周取两侧坐骨神经和L4、L5、L6的DRG,分别在光镜和电镜下观察病理变化,采用激光捕获显微切割（LCM）结合寡核苷酸基因芯片技术研究DRG神经元的基因表达谱.结果 神经病理显示,坐骨神经冷损伤后第7天时,已出现明显的以大纤维为主的神经变性;第14天时,有髓纤维密度显著减少,已可见再生纤维;冷损伤后第21天,坐骨神经已经有明显的再生,小直径的有髓纤维增多.冷损伤后第14天对DRG神经元进行基因表达谱分析,显示96个基因表达差异达2倍以上（P＜0.05）,均上调.其功能涉及对外界刺激的适应性反应、凋亡的调节、细胞黏附因子、免疫和炎性反应、神经再生相关、疼痛、细胞骨架、离子通道类、神经递质及受体等.结论 大鼠坐骨神经冷损伤和修复是由大量的基因参与的复杂过程,应用基因芯片是全面揭示其分子机制的有效方法.Objective To investigate the morphological changes in the sciatic nerve and the dorsal root ganglions （DRGs） and also gene expression in DRGs after non-freezing cold injury, and to explore the molecular mechanism of peripheral nerve cold injury and regeneration. Methods Twenty-four male Wistar rats were used. The sciatic nerve on one side was cooled to 4℃ for 2 h, and the sciatic nerve on the opposite side was exposed, but without cooling. Sciatic nerves and L4, L5 and L6 DRGs from both sides were harvested at the 1st, 2nd and 3rd week after cooling. Any pathological changes were observed using light and electron microscopy. Laser capture microdissection （LCM） was used to investigate the DRG neurons＇ gene expression. The array result was verified with RT-PCR for eight genes. Results Large fiber degeneration was obvious by the 7th day after cooling. Myelinated fiber regeneration had begun by the 14th day, so this time was chosen to explore the neurons＇ gene expression. Ninety-six genes and expressed sequence tags （ESTs） were up-regulated greater than 2 fold. Their proteins＇ functions were classified as adaptive response to external stimulus, apoptosis regulation, cell adhesion, immune and inflammation response,nerve regeneration, pain associated molecules, microtubule cytoskeleton, ion-channels, neurotransmitters and receptors, and neuropeptides. Conclusions A complex molecular mechanism is involved in cold injury and regeneration of the sciatic nerve, and many genes are involved. Large scale microarray analysis is a potent means to screen out related genes, thus suggesting future repair strategies.

关 键 词：冷损伤 周围神经 基因表达 基因芯片 激光捕获显微切割 

分 类 号：R651.3[医药卫生—外科学]