Neurogenesin1基因对脊髓损伤大鼠运动功能的影响及机制探讨  

EFFECTS OF NEUROGENESIN 1 GENE ON FUNCTIONAL RECOVERY OF SPINAL CORD INJURY IN RATS AND ITS MECHANISM

作　　者：郑张安[1] 尹宗生[1] 高维陆[1] 张辉[1] 胡勇[1] 张胜权[2] 

机构地区：[1]安徽医科大学第一附属医院骨科,合肥230032 [2]安徽医科大学分子生物学教研室

出　　处：《中国修复重建外科杂志》2010年第4期410-414,共5页Chinese Journal of Reparative and Reconstructive Surgery

基　　金：国家自然科学基金资助项目(30772201)~~

摘　　要：目的观察Neurogenesin1(Ng1)基因对大鼠脊髓损伤后功能恢复的影响,并初步探讨其可能机制。方法4月龄SPF级SD大鼠36只,体重约230g,雌雄不限,随机分为实验组和对照组(n=18)。采用改良Allen法制备大鼠T10脊髓损伤模型,通过Alzet微渗透压泵分别向实验组和对照组持续转染重组Ng1质粒和空白质粒各5μg。术后1d及1、2、3、4周采用BBB运动功能评分系统检测大鼠运动功能恢复情况;术后1周分别采用RT-PCR和Western blot方法检测Ng1mRNA及蛋白的表达;并于术后2、4周采用免疫荧光双标染色和组织学观察Ng1基因对内源性神经干细胞增殖的影响以及脊髓组织病理变化情况。结果自术后1周起实验组BBB评分明显高于对照组(P<0.05);术后4周实验组运动功能评分为(16.80±1.79)分,对照组为(9.60±1.67)分,差异有统计学意义(P<0.01)。RT-PCR和Western blot方法检测显示实验组大鼠脊髓组织均见Ng1mRNA与蛋白的表达,对照组无表达。组织学观察示实验组脊髓结构以及神经元形态恢复较好且逐渐趋于正常,且免疫荧光双标染色示实验组脊髓组织中新增殖的神经干细胞数较对照组明显增多,差异有统计学意义(P<0.05)。结论Ng1基因能够诱导脊髓损伤后内源性神经干细胞大量增殖,保护受损伤神经元,促进脊髓运动功能修复。Objective To explore the effects of Neurogenesin 1（Ng1）gene on functional recovery after spinal cord injury（SCI）and its mechanism.Methods Thirty-six rats（aging 4 months,weighing 230 g and being male or female）,were randomly divided into two groups：experimental group（n=18）and control group（n=18）.After spinal cord contusive injury at T10 level was made in all these rats using modified Allen＇s method,Ng1 recombinant plasmid and blank plasmid were transfected into the damaged areas of exprimental group and control group respectively by Alzet pumps.At 1 day,1 week,2 weeks,3 weeks,and 4 weeks after SCI,Basso-Beattle-Bresnahan（BBB）Rating Scale was used to observe the recovery of motor function.At 1 week after injury,the expressions of Ng1 mRNA and protein in injured spinal cord were detected by RT-PCR and Western blot techniques.And at 2 and 4 weeks,double immunofluorescence and histopathologic examinations were performed to study the proliferation of the adult endogenous neural stem cells and pathological change after SCI.Results At 1-4 weeks after SCI,the BBB scores in the exprimental group was significantly higher than that in control group（P0.05）,and at 4 weeks the BBB score of the experimental group（16.80±1.79）was significantly higher than that of the control group（9.60±1.67）,（P0.01）.RTPCR and Western blot showed that the mRNA and protein expressions of Ng1 were observed in the exprimental group and no expression was seen in the control group.Histologic observation showed that the morphology of spinal cord and neurons in the exprimental group was better than that in the control group and was close to the normal tissue.The mean number of Nestin＋/BrdU＋newborn endogenous neural stem cells in the exprimental group was significantly more than that in control group（P0.05）.Conclusion Ng1 gene could promote the proliferation of endogenous neural stem cells and protect the injured neurons,which enhances the repair of the motor function after SCI.

关 键 词：Neurogenesin1基因 神经干细胞 脊髓损伤 大鼠 

分 类 号：R651.2[医药卫生—外科学]