坐骨神经横断伤后远侧段组织的形态学及相关因子表达变化  

The changes in morphology and relevant factors expression in the distal segments after sciatic nerve transection

作　　者：刘恩辰[1] 王鸿奎[1] 王亚先[1] 张沛云[1] 顾晓松[1] 

机构地区：[1]南通大学江苏省神经再生重点实验室,江苏226001

出　　处：《交通医学》2011年第1期1-8,共8页Medical Journal of Communications

基　　金：863重大项目(2006AA02A128);江苏省自然科学创新学者攀登项目(BK2008010)

摘　　要：目的:通过制备GFP小鼠和B6小鼠坐骨神经横断伤模型,应用免疫组化技术以及RealTime-PCR技术观察和分析周围神经损伤后远侧段组织的形态学及相关因子表达变化。方法:制备GFP小鼠坐骨神经横断伤模型,应用免疫组化技术分别染色S100蛋白以显示施万细胞,染色NF蛋白以显示轴突;结合GFP小鼠的自发荧光以及Hoechst核染观察横断伤后不同时间点远侧段组织的形态学变化。制备B6小鼠坐骨神经横断伤模型,应用RealTime-PCR技术检测横断伤后远侧段组织中相关营养因子BDNF、NGF、CNTF及抗凋亡因子Bcl-2 mRNA的表达变化。结果:坐骨神经横断伤后,远侧段施万细胞S100蛋白的表达第7天时达到高峰,第14天时下降,形成狭长细胞索带;第21～28天时仅少数细胞S100蛋白阳性。远侧段NF免疫组化产物于横断伤后第7天时断裂呈碎片状,第28天时碎片亦基本消失不见。远侧段非特异核染数目随损伤时间延长而增加。同时,在远侧段整个溃变过程中,神经基膜管结构仍然可见。坐骨神经横断伤后,BDNF mRNA表达第1～3周内逐渐上调,其中第3周时达到高峰(P<0.01),第4周时下降到与正常值相比无统计学意义的水平。NGF mRNA表达第1周时达到高峰(P<0.01),第2周时比第1周有小幅下降,但仍然具有统计学意义(P<0.01),第二周以后下降到与正常值相似的水平。CNTF mRNA表达则在损伤后第1周时下降了35%,第2周时继续下降到正常水平的42.7%,其下降均具有统计学意义(P<0.01),第3周时有所回升,第4周时下降到低点。Bcl-2 mRNA表达在损伤后第1周时下降,第2、3周时上升,第3周时达到高峰,并且上升具有统计学意义(P<0.01)。结论:坐骨神经横断伤后4周,远侧段神经组织中神经基膜管结构仍然存在。神经营养因子BDNF、NGF、CNTF mRNA的表达时相不同,提示其表达调控机制不同。Bcl-2 mRNA表达变化与施万细胞凋亡相关。Objective：To establish the model of GFP mouse and B6 mouse sciatic nerve transection,the immunohistochemistry and RT-PCR are applied to observe and analyze the morphological and the relevant factors changes in the distal segments post peripheral nerve injury.Methods：After the model of GFP mouse sciatic nerve transection was established,the proteins of S100 and NF were demonstrated respectively by using immunohistochemistry,the green autoflurescence and the Hoechst nucleus stain to observe the morphological changes in the distal segments at different time points after sciatic nerve transection.After B6 mouse sciatic nerve was transected,RT-PCR was performed to detect the mRNA expression changes of BDNF,NGF,CNTF,and Bcl-2 in the distal segments of injured nerve.Results：After sciatic nerve transection,the Schwann cells showed the highest level of S100 protein in the distal segments on day 7,the expression of S100 protein decreased on day 14,and the slender cells＇ belt emerged.Only a few cells were S100 positive at days 21～28.The spot-like fragments of NF protein in the distal segments emerged on day 7 and the signals were completely absent on day 28.The nucleu number stained by Hoechst in the distal segment gradually increased after transection.Meanwhile,the nerve basal lamina tube could be seen during the whole degenerative process.After sciatic nerve transection,the mRNA level of BDNF was gradually upregulated from week 1 to week 3,and peaked in week 3（P0.01）,but decreased to the level of no statistical significance compared to the normal in week 4.The mRNA level of NGF reached the highest level in week 1,slightly decreased in week 2,but still had the significantly higher level compared to the normal.After 2 weeks,the NGF mRNA level dropped to the level similar to the normal.The CNTF mRNA expression declined 35% in week 1,and went on decreasing to the 42.7% of the normal,rose again in week 3,but dropped to a low level in week 4.Bcl-2 mRNA level declined in week 1,but was significantly upregulated at

关 键 词：坐骨神经横断伤 GFP小鼠 远侧段 华勒氏变性 神经基膜管 相关因子 

分 类 号：R651.3[医药卫生—外科学]