雪旺细胞源神经营养因子预防臂丛神经根性撕脱伤所致 …

目的 研究雪旺细胞源细胞神经营养因子（ＳＤＮＦ）对臂丛神经根性撕脱伤所致前角运动神经元死亡的保护作用。方法 选成年ＳＤ大鼠,制成颈６、７神经根性撕脱伤动物模型,损伤处定期应用ＳＤＮＦ,３周后观察损伤侧脊髓前角运动神经元的成活率和形态学变化,以及一氧化氮合酶（ＮＯＳ）表达的情况。结果 对照组６８．６％的脊髓前角运动神经元死亡,成活神经元胞体明显萎缩,同时表达ＮＯＳ神经元增多;实验组脊髓前角运动神经元     

雪旺细胞源神经营养因子对脊神经根性撕脱所致运动神经元死亡的保护作用

目的研究雪旺细胞源神经营养因子（ＳＤＮＦ）对臂丛神经根性撕脱所致前角运动神经元死亡的保护作用。方法于颈神经根性撕脱处应用ＳＤＮＦ,３周后观察损伤侧脊髓前角运动神经元的存活率和形态学变化以及ＮＯＳ表达的情况。结果对照组６８．６％的神经元死亡,存活神经元胞体明显萎缩,同时表达ＮＯＳ神经元增多;实验组的死亡率较对照组降低３５％,存活神经元胞体无萎缩,表达ＮＯＳ神经元未见增多。结论ＳＤＮＦ对脊髓前角运动神经元死亡有明显的保护作用,ＮＯ在臂丛神经根性撕脱所致运动神经元死亡中起一定作用。     

雪旺细胞源神经营养因子对脊神经根性撕脱所致运动神经元 …

目的 研究雪旺细胞源神经营养因子对臂丛神经根性撕脱所致前角运动神经元死亡的保护作用。方法 于颈神经根性撕脱处应用ＳＤＮＦ,３周后观察损伤侧脊髓前角运动神经元的存活率和形态学变化以及ＮＯＳ表达的情况。结果 对照组６８．６的神经元死亡,存活神经元胞体明显萎缩,同时表达ＮＯＳ神经元增多;实验组的死亡率较对照组降低３５％,存活神经元胞体无萎缩,表达ＮＯＳ神经元未见增多。     

条件性损伤对脊神经根撕脱伤后脊髓运动神经元一氧化氮合 …

目的 探索条件性损伤对脊神经根撕脱后脊髓前角运动神经元一氧化合酶（ＮＯＳ）表达及神经细胞死亡的影响。方法 雌性ＳＤ大鼠７８只,分为两组,实验组在臂丛神经干压榨术后１周行神经根撕脱术;对照组仅施行神经根撕脱术,术后３ｄ～８周于不同时间点处死动物,取Ｃ５～Ｃ６节段脊髓,行ＮＡＤＰＨ－ｄ组化染色,中性红复染。结果 单纯神经根撕脱组术后第５ｄ脊髓前角运动神经元开始表达ＮＯＳ,至术后２周ＮＯＳ阳性神经元数达     

实验性不同类型大鼠臂丛根性损伤后脊髓运动神经元存活情况观察

目的 研究臂丛神经根性切断伤与根性撕脱伤后脊髓前角运动神经元的存活情况。方法 对76只健康成年SD大鼠,按手术先后顺序分成臂丛神经根性切断伤组和根性撕脱伤组,两组按术后9个不同的时间组取材,每组4只大鼠,共72只大鼠。另外4只为正常对照组。取了脊髓标本后,观察颈髓前角运动神经元数目的变化。结果 臂丛神经根性切断伤后,各时间组的脊髓前角运动神经元数目和术前无明显变化;而根性撕脱伤组于术后1周其神经元数目开始减少,术后2周时神经元数目比正常对照组减少30％,术后6周时减少70％。撕脱伤组与切断伤组相比,损伤1周后,各时间组的差异均有显著性意义（X^2＝3．922－17．21,P＜0．01）。结论 臂丛神经根性切断伤其脊髓运动神经元和术前比无明显变化,而臂丛神经性撕脱伤后其脊髓运动神经元有死亡,死亡速度快,死亡程度高。     

臂丛损伤神经干细胞脊髓前角移植后分化情况及对运动神经元的保护作用

目的观察臂丛根性撕脱伤后将脊髓源性神经干细胞(neuralstemcell,NSC)移植于脊髓前角后的存活、分化情况及对脊髓前角受损运动神经元的保护作用。方法取新生鼠脊髓,分离获得脊髓源性神经干细胞,体外培养、扩增、鉴定、5溴2-脱氧尿苷(BrdU)标记。取SD大鼠60只,随机分成实验组、对照组和单纯组。从后路制备C5~C7臂丛神经根性撕脱伤动物模型。实验组移植神经干细胞于C6脊髓前角,对照组移植灭活神经干细胞,单纯组不作移植。术后1、2、4、8、12周取脊髓标本进行组织学与免疫组化染色观察。结果神经干细胞移植入脊髓后能存活、分化;臂丛根性撕脱伤后脊髓前角运动神经元数目明显减少;实验组神经干细胞移植后2、4、8、12周各个时间点运动神经元的存活率均高于对照组和单纯组。结论臂丛根性撕脱伤脊髓前角神经干细胞移植后能存活并分化为神经元及星型胶质细胞,脊髓源性神经干细胞移植能明显减少前角运动神经元的继发性死亡,对脊髓前角受损运动神经元有保护作用。     

臂丛根性损伤脊髓前角α运动神经无数目变化的实验研究

以Sprague-Dawly大鼠为研究对象，设计臂丛根性撕脱伤的实验模型，研究臂丛根性撕脱后脊髓前角α运动神经元数目变化。实验结果表明：臂丛根性撕脱伤后脊髓前角α运动神经元死亡23．7％。     

臂丛神经根性撕脱伤后神经营养因子在脊髓及肌肉中表达的变化

目的：通过观测臂丛神经根性撕脱伤后脊髓前角运动神经元及肌肉组织内神经营养因子表达的变化。探讨臂丛神经撕脱伤后中枢运动神经元,靶器官的功能改变可能对神经再生产生的影响。方法：清洁级Wistar大鼠48只,随机分成正常对照组和损伤术后1天,1,4,8和12周共六组,损伤组均从前路造成臂丛颈5,6,7神经根性撕脱伤,按各组所示时间取脊髓及肌肉分别检测碱性成纤维细胞生长因子（bFGF)蛋白及mRNA,神经生长因子（NGF）蛋白的表达,并采用计算机图像分析系统对组织切片中bFGF蛋白及mRNA,NGF蛋白进行半定量分析,比较,结果：臂丛神经根性撕脱伤后,肱二头肌内NGF蛋白表达增高,1天时达到高峰,随后下降,3个月时仍高于对照组,而脊髓前角运动神经元bFGF蛋白及mRNA的表达在伤后亦升高,1周时达到高峰,随后下降,3个月时下降到稍低于正常水平,结论：臂丛神经根性撕脱伤后神经营养因子在中枢神经元及靶器官内表达增高,可能起保护神经元,促进神经再生的作用。     

大鼠臂丛神经根性回植后脊髓病理改变和轴突再生

目的 探讨臂丛神经根性撕脱后神经根再植入脊髓的可行性。方法 采用大鼠颈5-7，神经根性撕脱伤实验动物模型，伤后将C5-7，神经根即刻植入脊髓。分别于神经根植入后3周、3个月、6个月取材。应用组织病理活检、免疫组化技术及神经示踪技术，对神经中枢及吻合口下段神经干检查。观察脊髓前角运动神经元和神经元内尼氏体数目和形态的改变；周围神经纤维再生数目、距离，轴索和髓鞘发育情况。结果 臂丛神经根性撕脱伤对动物生长和存活有较大的影响。脊髓前角运动神经元数目在3个月内持续减少，3个月后趋于稳定，6个月时脊髓前角大型运动细胞坏死比率在40％左右，残存的神经元多为受损的神经元，尼氏体减少或消失。脊髓前角运动神经元再生轴突可重新生长入周围神经干，再生神经纤维轴索较细，大部分髓鞘发育不完全，轴突再生距离较短，肌皮神经6个月内无神经纤维再生。结论 臂丛神经根性撕脱伤，神经根回植入脊髓后，脊髓前角运动神经元坏死比率为40％左右，残存神经元多为受损神经元，再生神经纤维表现为动力不足和发育不全，对终末器官功能恢复没有意义。     

细胞外ATP对臂丛神经根性撕脱伤后脊髓运动神经元保护的实验研究

目的 观察细胞外ATP对臂丛神经根性撕脱伤所致脊髓前角运动神经元损伤的保护作用. 方法 Wistar大鼠36只,随机分为两组:单纯神经根撕脱组和神经根撕脱加ATP治疗组.行左侧臂丛神经根性撕脱术,术后实验组腹腔注射ATP(2 mg/kg)0.4 nd,对照组腹腔注射生理盐水0.4 ml,均为1次/日,连续应用ATP或生理盐水2周.术后2周、4周和6周后取材,处死动物后取C5～C8脊髓分别行一氧化氮合酶(NOS)、神经丝蛋白(NF-200)免疫组织化学染色. 结果 术后2、4和6周,实验组脊髓前角运动神经元存活率为80.48%、73.55%、53.43%,对照组为68.90%、63.58%、37.72%,实验组与对照组比较脊髓前角运动神经元死亡率分别降低了11.58%、9.87%和15.71%(P<0.01);实验组脊髓前角运动神经元中NOS阳性率为17.85%、40.20%、18.03%,对照组为25.53%、53.88%、25.58%,实验组与对照组比较.脊髓前角运动神经元中NOS阳性率分别下降了7.68%(P<0.01)、13.68%和7.55%(P<0.05);实验组脊髓前角运动神经元的NF-200阳性细胞数均高于对照组,两者比较差异有统计学意义. 结论 ATP对臂丛神经根性撕脱伤后脊髓前角运动神经元具有保护作用.     

许旺细胞源神经营养因子对脊髓前角运动神经元的保护作用

目的 了解许旺细胞源神经营养因子对神经损伤所致脊髓前角运动神经元死亡的保护作用。方法 选用出生３周ＳＤ鼠切断坐骨神经,神经近侧行旺细胞源神经营养因子或生理盐水,４周后观察腰４－５节段脊髓前角运动神经元的存活率和一氧化氮合成酶表达情况。结果术后４周,营养因子组神经元的存活率是９３．４％,生理盐一是５９．６％,两组一氧化氮合酶表达均未见增加。结论 许旺细胞源神经营养因子对员的俏髓前角运动神经元有明显     

GDNF and BDNF alter the expression of neuronal NOS,c-Jun,and p75 and prevent motoneuron death following spinal root avulsion in adult rats

In the present study, we examined the effects of glial cell line-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), and insulin growth factor (IGF-1) on adult motoneuron survival following spinal root avulsion. The expression of neuronal nitric oxide synthase (nNOS), c-Jun, and the low-affinity neurotrophin receptor (P75) following treatment with these neurotrophic factors was also examined. In control animals, approximately 80% of spinal motoneurons were nNOS positive at 3 weeks following the lesion, whereas in GDNF or BDNF treated animals no nNOS positive motoneurons were found at the same time point. Following injury and treatment with GDNF and BDNF increased numbers of motoneurons were c-Jun and P75 positive. By 6 weeks following the lesion, only approximately 28% of motoneurons persisted in control animals whereas about 90% of motoneurons survived injury following treatment with either GDNF or BDNF. In contrast, CNTF and IGF-1 were ineffective in either inhibiting nNOS expression or preventing motoneuron death. Our results provide in vivo evidence that the survival of injured adult mammalian motoneurons can be promoted by specific neurotrophic factors, and that this effect is associated with inhibition of nNOS expression and up-regulation of c-Jun and P75 expression.     

Survival of injured spinal motoneurons in adult rat upon treatment with glial cell line-derived neurotrophic factor at 2 weeks but not at 4 weeks after root avulsion

We conducted a study of whether treatment with glial cell line-derived neurotrophic factor (GDNF) initiated at 2 or 4 weeks after spinal-root avulsion could promote survival and regulate neuronal nitric oxide synthase (nNOS) expression in adult rat spinal motoneurons. By 6 weeks after root avulsion, the treatment given at 2 weeks not only increased motoneuron survival (86.1% vs. 27.9%), but also reversed the atrophy of injured motoneurons and increased their somatic size (101.3% vs. 52.9%) in comparison to the untreated control group of animals. All surviving motoneurons in the GDNF-treated group showed immunoreactivity for choline acetyltransferase. In contrast, GDNF treatment at 4 weeks post-injury failed to promote motoneuron survival (33.1% vs. 27.9%) at 6 weeks compared to the control group. Both the 2- and 4-week post-injury treatments downregulated nNOS expression. This finding suggests that injured adult motoneurons die shortly (a few weeks in the rat) after root avulsion injury, but can be saved from degeneration by treatment within the proper time frame after injury, which in the case of GDNF treatment in rats, appears to be within 2 weeks of the avulsion injury of the spinal root. These findings provide useful information for choosing the best time frame for the potential clinical treatment of brachial plexus avulsion.     

Valproic acid protection against the brachial plexus root avulsion‐induced death of motoneurons in rats

In this study, the role of valproic acid (VPA) in protecting motoneuron after brachial plexus root avulsion was investigated in adult rats. Sixty rats were used in this study, and underwent the brachial plexus root avulsion injury, which was created by using a micro‐hemostat forceps to pull out brachial plexus root from the intervertebral foramen. The animals were divided into two groups, VPA group administered with VPA dissolved in drinking water (300 mg/kg) daily, and control group had drinking water every day. The spinal cords (C5‐T1) were harvested at day 1, 2, 3, 7, 14, and 28 for immunohistochemistry analysis, TUNEL staining, Nissl staining, and electron microscopy, respectively. The results showed that with VPA administration, the survival of motoneurons was promoted and the cell apoptosis was inhibited. The number of c‐Jun and Bcl‐2 positive motoneurons was increased immediately after avulsion both in control and VPA group, however, the percent of c‐Jun positive motoneurons was decreased and the percent of Bcl‐2 positive motoneurons was increased by VPA treatment significantly. Our results indicated that motoneurons were protected by VPA against cell death induced by brachial plexus root avulsion through c‐Jun inhibition and Bcl‐2 induction. © 2013 Wiley Periodicals, Inc. Microsurgery 33:551–559, 2013.     

雪旺细胞源神经营养因子的神经营养活性及其抗NO神经毒性作用

目的：研究雪旺细胞源神经营养因子对脊髓前角神经元的神经营养活性及对抗一氧化氮（ＮＯ）神经细胞毒性的作用。方法：分４组进行神经元培养：（１）营养因子组：加入不同浓度的雪旺细胞源神经营养因子；（２）ＮＯ组：加入ＮＯ体外供体硝普钠；（３）营养因子＋ＮＯ组：同时加入雪旺细胞源神经营养因子和硝普钠：（４）对照组：加Ｄ－Ｈａｎｋ，培养２天后，ＭＴＴ法观察各组细胞情况。结果：营养因子组ＯＤ值均明显高于对照组；ＮＯ组ＯＤ值明显低于对照组：营养因子＋ＮＯ组，当神经营养因子浓度大于３０ｎｇ·孔－１时，ＯＤ值显著高于ＮＯ组。结论：ＮＯ抑制体外培养脊髓前角神经元的存活；雪旺细胞源神经营养因子对体外培养脊髓前角神经元具有明显的神经营养活性，且能对抗ＮＯ的神经细胞毒性。     

神经干细胞对脊髓前角运动神经元保护作用的实验研究

目的观察臂丛根性撕脱伤后神经干细胞脊髓内移植对前角运动神经元的保护作用。方法取孕龄15～18d胎鼠脑组织，分离获得神经干细胞，在体外培养、扩增，并用5溴-2脱氧尿苷(BrdU)标记。取Wistar大鼠72只，随机分成实验组与对照组。先将C5～T1神经根撕脱，实验组把体外培养的神经干细胞移植于C5～T1脊髓节段前角附近，而对照组则用缓冲液替代神经干细胞。术后1、2、4、6、8、12周取脊髓标本进行组织学与免疫组化染色观察。结果臂丛根性撕脱伤后脊髓前角运动神经元数目明显减少，到术后12周时，对照组运动神经元减少达80．3％，实验组达63．7％。并且，各时间点实验组运动神经元的存活率均高于对照组。实验组脊髓前角内可见散在但仍保持未分化特征的神经干细胞。结论神经干细胞在植入臂丛根性撕脱伤的脊髓后能存活，并能明显减少前角运动神经元的继发性死亡。