脊髓损伤后脂质蓄积对损伤灶自发荧光强度的影响

目的 :研究小鼠脊髓损伤后损伤灶的脂质蓄积与自发荧光强度之间的关系,探索硫酸铜能否消除脊髓损伤灶的自发荧光。方法:选取鼠龄8~12周,体重18~24 g的野生型小鼠36只,随机分为正常对照组(4只)与脊髓损伤组(32只)。脊髓损伤组于损伤后1、2、4、8周分别随机抽取8只处死,以损伤灶为中心取脊髓组织标本行冰冻切片(正常对照组取相同节段的脊髓,标本放入4%多聚甲醛溶液进行后固定),在荧光显微镜的绿色通道下观察自发荧光,进行油红O染色显示损伤灶的脂质蓄积,并分析自发荧光强度与脂质蓄积量的相关性。配制硫酸铜缓冲液处理切片以消除自发荧光,并优化硫酸铜浓度与作用时间。结果:正常脊髓组织切片未发现明显自发荧光或脂质染色,而脊髓损伤后在损伤灶出现自发荧光,并且强度随损伤后时间延长而增强。油红O染色显示损伤灶的脂质同样随伤后时间延长而蓄积,并且增长趋势与自发荧光的增强趋势呈正相关。应用硫酸铜缓冲液后,自发荧光强度显著降低,优化硫酸铜浓度与作用时间后效果更好。结论:脊髓损伤后损伤灶脂质蓄积可能在决定自发荧光的强度上起重要作用,自发荧光强度可以作为评估脂质过氧化损害的简便指标;优化的硫酸铜法能够显著消除脊髓损伤后损伤灶的自发荧光,有利于免疫荧光染色技术在脊髓损伤研究中的应用。     

嗅鞘细胞移植后在脊髓中迁移特性的研究

目的: 观察移植的嗅鞘细胞 (OECs) 在损伤脊髓中的迁移特性。方法: 将OECs用双苯亚甲胺染色, 植入 12只SD大鼠半横断脊髓的头端 (A组 ), 植入 12只大鼠半横断脊髓的尾端 (B组 ), 对照组(C组) 12只植入没有损伤的脊髓内。术后 1、2、4、6周观察脊髓中OECs的分布。结果: A组和B组OECs分别在白质中向头端和尾端迁移, 但越过断端的数量少, C组不迁移。结论: OECs的迁移主要沿着轴突进行, 向头端和尾端迁移的数量和速度都没有明显区别, 但 6周时只有少量OECs能越过损伤区。OECs在没有损伤的脊髓白质中不进行迁移。     

大鼠脊髓三种不同损伤后神经细胞凋亡的实验比较

目的了解三种不同脊髓机械性损伤对继发性神经细胞凋亡的影响。方法采用脊髓挫伤、持续性占位、脊髓横断三种大鼠损伤模型,在伤后1、4、7d观察损伤断面神经细胞凋亡现象。结果脊髓挫伤组:灰质三个时间组的凋亡指数波动明显,灰质中凋亡指数4d时最高;白质中凋亡细胞除背侧束外腹侧束也存在;另外细胞凋亡以少突胶质细胞凋亡为主。脊髓持续性占位损伤组:灰质、白质细胞凋亡指数在4d和7d组中差异无显著性意义(P>0.05),白质凋亡细胞在受压的背侧束、外侧束为主。脊髓横断损伤组:灰质、白质在三个时间组中均有大量凋亡细胞。结论大鼠脊髓损伤后神经细胞虽然存在主动死亡(细胞凋亡)方式,但凋亡在时间和部位上与损伤类型、损伤部位、损伤程度有关。     

大鼠脊髓损伤后骨形态发生蛋白2表达变化的规律及意义

目的:观察大鼠脊髓损伤后损伤脊髓组织中骨形态发生蛋白2(BMP2)表达变化的时间及空间分布规律,探讨抑制BMP2增加的最佳时间及部位。方法:成年SD大鼠40只,随机分为5组:假手术组,损伤后1d组、3d组、7d组、14d组,每组8只。将大鼠麻醉后以T10棘突为中心,打开椎板,暴露脊髓,各损伤组使用NYU impactor打击器制作大鼠脊髓损伤模型,假手术组不做打击处理。分别于造模前后对各组大鼠进行运动功能BBB评分,于预定时间点处死动物,取损伤段(假手术组取相应节段)脊髓组织行HE染色和免疫组化染色,观察脊髓组织学改变并进行阳性细胞计数,采用方差分析进行组间比较。结果:造模前各组大鼠的BBB评分均为21分;造模后假手术组大鼠BBB评分高于各损伤组,且差异有显著性(P<0.01),各损伤组之间两两比较评分均无显著性差异(P>0.05)。HE染色假手术组大鼠脊髓组织结构清晰,层次规整,条理性强,灰质中可见较多的神经元,白质中可见大量纤维性星形胶质细胞;损伤组大鼠损伤处脊髓组织结构紊乱,层次感消失,可见弥散的血细胞,早期增多较晚期明显,脊髓灰质与白质中都可见因大量组织细胞溶解而遗留的组织空洞。各组脊髓灰、白质中均有BMP2表达,假手术组灰质中平均阳性细胞数为1.53±0.38个/HP,白质中为0.77±0.14个/HP;损伤后1d组灰质中为13.70±4.81个/HP,白质中为7.23±3.14个/HP;损伤后3d组灰质中为9.37±3.61个/HP,白质中为5.63±2.23个/HP;损伤后7d组灰质中为6.17±1.81个/HP,白质中为4.17±1.24个/HP;损伤后14d组灰质中为4.36±1.60个/HP,白质中为1.87±1.13个/HP;损伤各组BMP2平均阳性细胞数与假手术组相比较均有明显差异(P<0.01),各组灰质区BMP2平均阳性细胞数的增加均较白质区更为显著(P<0.01)。结论:脊髓损伤后损伤脊髓组织中BMP2的表达增加,损伤后1d最高,主要集中在损伤区灰质区。针对BMP2进行特异性抑制最好在损伤后第一天的脊髓灰质区实施。     

氢饱和生理盐水对兔脊髓缺血再灌注损伤的神经保护作用

目的 研究氢气对脊髓缺血再灌注损伤的保护作用及其潜在机制。方法 新西兰兔随机分为3组：对照组、脊髓缺血再灌注损伤组和氢水治疗组。对照组仅接受暴露,无脊髓缺血再灌注损伤;缺血再灌注组动物采用ZIVIN法建立脊髓缺血再灌注损伤模型,造成脊髓腰骶段缺血35 min 后行再灌注;氢水治疗组动物在再灌注前5 min腹腔注射饱和氢盐水（5 mL/kg）,再灌注后8 h重复注射。不同时间点检测后肢运动功能。术后72 h取脊髓进行HE染色、TUNEL染色、氧化-抗氧化指标检测及ELISA检测细胞因子。结果 含氢生理盐水治疗能显著改善动物神经功能、抑制脊髓神经元凋亡、抑制氧化应激、改善抗氧化能力,同时降低炎症相关细胞因子,从而发挥脊髓保护作用。结论 腹腔注射含氢生理盐水通过抗氧化和抗炎对脊髓缺血再灌注损伤发挥保护作用。     

环孢霉素A对大鼠脊髓损伤早期环氧化酶-2与肿瘤坏死因子α表达的影响

目的:观察环孢霉素A(CsA)对大鼠脊髓损伤(SCI)早期环氧化酶-2(Cox-2)与肿瘤坏死因子α(TNF-α)表达的影响,探讨CsA对大鼠SCI的作用。方法:180只大鼠随机分成对照组、损伤组和损伤后CsA治疗组(治疗组),每组60只。用25g.cm致伤损伤组和治疗组大鼠T8~T11脊髓,对照组不损伤脊髓。治疗组于术后1h予尾静脉注射CsA(2.5mg/kg),之后每隔12h给药1次,对照组和损伤组在相同时间点尾静脉注射相同体积生理盐水。损伤组和治疗组于术后2h、6h、12h、24h、48h和72h处死动物取损伤段脊髓标本,对照组在相应时间点取相应节段脊髓标本,切片后分别行HE染色观察脊髓组织损伤情况、免疫组织化学EnVision法检测TNF-α、免疫组织化学SP法检测Cox-2,并对TNF-α和Cox-2进行定量分析。结果:对照组各时间点脊髓无出血、水肿等变化。损伤组和治疗组伤后2h、6h脊髓灰质可见水肿、出血,但无坏死,周围白质无明显改变;12h、24h脊髓灰质出现广泛灶性出血及出血后形成囊腔,神经元肿胀,部分细胞核浓缩,染色增强,白质见少量红细胞渗出,髓鞘轻度肿胀;48h、72h脊髓灰质中出现神经元固缩、坏死、溶解,细胞体积变小,有大量小胶质细胞增生和中性粒细胞浸润,白质中可见较多红细胞渗出,髓鞘肿胀和大量空泡,周围有炎性细胞浸润和胶质细胞增生;治疗组各时间点的病理改变均较损伤组轻。对照组大鼠脊髓Cox-2呈可疑阳性表达;损伤组和治疗组伤后2h Cox-2即有表达,6h达到高峰,之后逐渐下降;损伤组在伤后72h Cox-2表达仍较对照组高(P<0.05),而治疗组到伤后48h即恢复到对照组水平(P>0.05),治疗组各时间点Cox-2表达均较损伤组低(P<0.05);对照组大鼠脊髓TNF-α呈可疑阳性或弱阳性表达;损伤组和治疗组伤后2h即有TNF-α表达,12h达到高峰,之后逐渐下降;损伤组在伤后72h TNF-α表达仍较对照组高(P<0.05),而治疗组在伤后72h即恢复到对照组水平(P>0.05),治疗组各时间点TNF-α表达均较损伤组低(P<0.05)。结论:CsA能显著降低大鼠SCI后早期损伤脊髓组织中Cox-2和TNF-α的表达,从而减轻脊髓继发性损伤。     

脊髓损伤后脑萎缩对运动功能恢复的影响

 目的 探讨脊髓损伤后脑部萎缩情况以及脑萎缩对患者运动功能恢复的影响。方法 回顾性分析2012年10月至2014年3月,25例接受脊柱内固定治疗的脊髓损伤患者完整随访资料,根据随访6个月后的运动功能恢复情况分为恢复较好组和恢复一般组,同时另选取25例年龄、性别相匹配的健康人作为对照组。恢复较好组10例,男6例,女4例;年龄24~55岁,平均（37.9±13.9）岁;入院时ASIA评级A级1例,B级4例,C级3例,D级2例;6个月后ASIA评级均有一个以上好转,其中A级0例,B级1例,C级3例,D级3例,E级3例;入院时ASIA运动评分为（71.9±16.3）分,6个月后为（85.5±1.5）分。恢复一般组15例,男8例,女7例;年龄24~55岁,平均（35.8±11.5）岁;入院时ASIA评级A级7例,B级3例,C级3例,D级2例）;6个月时ASIA评级未见明显改善;入院时ASIA运动评分为（71.9±16.3）分,6个月后为（85.5±1.5）分。对照组25名,男15名,女10名,年龄（36.5±9.3）岁。采用MRI扫描三组受试者脑部结构信息,运用CIVET软件及DtiStudio软件对比三组大脑灰质和白质萎缩的区域。运用Pearson相关性分析探讨脑皮层萎缩与患者运动功能恢复率之间的相关性。结果 与健康对照组相比,脊髓损伤恢复较好组和恢复一般组均存在双侧初级运动皮层的灰质萎缩,但恢复一般组的萎缩程度更广泛和严重,同时还出现右侧辅助运动区和运动前区的灰质萎缩。恢复较好组未见明显的脑内皮质脊髓束萎缩,而恢复一般组脑内皮质脊髓束初级运动皮层区域及内囊区域均出现白质萎缩。此外,脊髓损伤患者辅助运动区的灰质体积（r=0.75,P< 0.001）及初级运动皮层的白质体积（r=0.76,P< 0.001）与患者6个月后的运动恢复率存在正相关关系。结论 在脊髓损伤早期,运动感觉中枢即可出现明显的萎缩现象,同时这种萎缩对患者的运动功能恢复存在不利影响。     

坐骨神经预损伤后miR-124-3p调节GAP-43表达并促进轴突生长的实验研究

 目的 通过研究坐骨神经预损伤后背根神经节中microRNA表达谱变化,探讨坐骨神经预损伤促进脊髓后索损伤修复机制。方法 利用微阵列芯片技术和生物信息学方法,研究与坐骨神经预损伤促进脊髓后索损伤修复有关的microRNA,并用RT-qPCR技术、Western blot技术、免疫荧光染色、反义miRNA寡核苷酸抑制剂等技术验证。结果 单纯脊髓后索损伤组miR-124-3p在大鼠脊髓后索损伤后7 d、14 d明显上调;坐骨神经预损伤组,脊髓后索损伤后7 d、14 d背根神经节中miR-124-3p明显下调。与正常背根神经节神经元相比,抑制miR-124-3p后GAP-43表达增加,神经元轴突延长。与对照组相比,各组各时间窗STAT3 mRNA表达差异无统计学意义,坐骨神经预损伤组STAT3蛋白在脊髓后索损伤后7 d和14 d表达上调而单纯脊髓后索损伤组脊髓后索损伤后7 d和14 d STAT3蛋白表达下调。与正常背根神经节神经元相比抑制miR-124-3p的神经元STAT3免疫荧光增强、轴突延长,p-STAT3、GAP-43蛋白表达明显上调。与正常背根神经节神经元相比AG490+AMO-124共同处理的神经元轴突长度无明显差异,STAT3表达明显上调,而p- STAT3和GAP-43表达无明显差异。结论 背根神经节神经元中miR-124-3p下调通过STAT3蛋白的上调促使GAP-43蛋白表达增加是坐骨神经预损伤促进脊髓后索损伤修复的机制之一。     

吡拉西坦通过MAPK通路治疗大鼠脊髓损伤的疗效观察与机制研究

目的: 探讨吡拉西坦通过丝裂原激活蛋白激酶(mitogen-activated protein kinase,MAPK)通路治疗脊髓损伤大鼠的作用机制。方法: 将54只体重为80~100 g的6周龄SD雌性健康大鼠采用随机数字表法分为假手术组、脊髓损伤组、吡拉西坦组,每组18只。脊髓损伤组、吡拉西坦组使用打击器建立脊髓损伤模型,假手术组不损伤脊髓。吡拉西坦组按照5 ml·kg-1标准予尾静脉注射吡拉西坦,连续干预3 d,每日1次;其他2组注射等剂量、等次数、等时长的生理盐水。分别于术后1、3、7 d处死大鼠并取材,观察并比较大鼠脊髓损伤行为学评分(Basso,Beattie and Bresnahan locomotor rating scale,BBB)的变化,使用酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测脊髓炎症因子白细胞介素-6(interleukin-6,IL-6)、白细胞介素-10(interleukin-10,IL-10)、白细胞介素-1β(interleukin-1β,IL-1β)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平变化,HE染色观察脊髓损伤大鼠的形态学变化,免疫组化观察水通道蛋白-4(aquaporin 4,AQP4)表达水平,蛋白质免疫印迹法(western blotting,WB)观察脊髓损伤后MAPK信号通路在大鼠脊髓中的激活状态。结果: 假手术组1、3、7 d的BBB评分均为21分;脊髓损伤组分别为(1±1)、(4±1)、(7±2)分;吡拉西坦组分别为(1±1)、(5±1)、(9±2)分;脊髓损伤组与假手术组比较,差异有统计学意义(P<0.05);吡拉西坦组与脊髓损伤比较,差异有统计学意义(P<0.05)。HE染色结果显示,假手术组形态未见异常。脊髓损伤组在术后1 d时,脊髓组织出现出血、变性;术后3 d,脊髓组织内出现片状坏死区;术后7 d,脊髓组织开始缓慢修复。吡拉西坦组术后1 d,脊髓损伤出血面积较脊髓损伤组减小;术后3 d,坏死区域较脊髓损伤组减少,细胞核消失范围较脊髓损伤组缩小;术后7 d,脊髓开始缓慢恢复。假手术组大鼠造模后1、3、7 d脊髓组织中AQP4染色较淡;脊髓损伤组AQP4染色加深,面积增大;吡拉西坦组AQP4染色较脊髓损伤组变淡,较假手术组阳性细胞略增多,染色微深。造模第1、3、7天,脊髓损伤组IL-6,IL-10,IL-1β和TNF-α水平高于手术组和吡拉西坦组(P<0.05)。与脊髓损伤组比,吡拉西坦组HE染色脊髓出血及坏死区域面积减小,免疫组化显示AQP4染色变淡。WB结果显示,造模第3天,脊髓损伤组p-ERK,p-JNK和p-p38水平高于假手术组和吡拉西坦组(P<0.05)。结论: 吡拉西坦不仅在促进脊髓损伤后的运动功能恢复方面表现出显著效果,而且在减少病变面积、调节AQP4表达以减轻水肿,以及通过调控MAPK信号通路降低炎症反应方面均显示出积极的治疗潜力。     

基于TNFR/RIPK1通路探索紫草素对大鼠脊髓损伤的作用及机制

目的:初步探讨紫草素对大鼠急性脊髓损伤(spinal cord injury,SCI)后神经功能恢复的影响及作用机制。方法:将96只Sprague-Dawley(SD)雄性大鼠分为4组:假手术组,即A组;假手术+紫草素组,即B组;脊髓损伤+二甲基亚砜(dimethyl sulfoxide,DMSO)组,即C组;脊髓损伤+紫草素组,即D组;每组24只。C、D组采用钳夹法制作大鼠急性SCI 模型。所有大鼠硬膜下置管,A 组不给药,B组和D组造模后30 min 经导管注射紫草素100 mg·kg^-1,C组注射等量 DMSO,每日1次,至取材时间点。各组分别于造模后6、12 h和3 d 每组取8只大鼠,行 Basso-Beattie-Bresnahan(BBB)评分及造模后1、3、7、14、21 d行斜板实验,再处死动物取脊髓组织。造模后1 h 每组大鼠腹腔注射碘化丙啶(propidine iodide,PI)1 mg·kg^-1,术后24 h取材检测脊髓组织 PI 红染细胞数;24 h 时取材采用苏木素-伊红(haematoxylin eosin,HE)染色观察脊髓损伤情况,尼氏(Nissl)染色观察神经元存活数量,使用Western-blot技术检测 B细胞淋巴瘤-2(B cell lymphoma-2,Bcl-2)蛋白及凋亡相关蛋白受体相互作用蛋白激酶1(receptor-interacting protein kinase 1,RIPK1)的表达水平。结果:造模后A组和B组各时间点的 BBB 评分均正常,C、D组各时间点均低于A、B组,D组造模后12 h和3 d的 BBB 评分高于同时间点C组(P<0.05)。造模后12 h,D组PI 红染细胞较C 组明显减少,神经元崩解减轻(P<0.05)。造模后24 h,A 组和 B 组脊髓组织 HE 和 Nissl 染色正常,D 组脊髓组织损伤程度和存活神经元数量均优于 C 组(P<0.05)。Bcl-2、RIPK1蛋白在A 组、B 组表达很低; RIPK1 在C组表达明显增高,在D组表达明显下降,差异有统计学意义(P<0.05);Bcl-2蛋白在D 组表达高于C 组(P<0.05)。结论:紫草素可减轻大鼠急性SCI后的病理变化,改善行为学评分,促进脊髓神经功能恢复。其具体机制可能与抑制TNFR/RIPK1信号通路介导的坏死性凋亡有关。     

大鼠脊髓损伤后巢蛋白在脊髓组织中的表达

目的探讨大鼠脊髓损伤后巢蛋白(nestin)的表达规律及其意义。方法30只Wister成年大鼠,随机分为正常对照组(A组)、损伤组(B组)。采用Allen打击模型(25g·cm),在T10段造成急性脊髓损伤,于损伤后1d、3d、1周、4周、8周进行取材,对距离损伤中心5mm处脊髓进行nestin免疫组化检测。应用图像分析软件进行nestin阳性区域面积侧算。结果A组脊髓室管膜细胞只可见极少数细胞胞浆内nestin表达,白质中几乎无表达。B组中nestin于损伤后24h表达于室管膜以及软膜,灰质和白质亦有少量表达,1周达到高峰(P<0.05),4周明显下降,8周时很少或几乎无表达。结论脊髓组织的许多部位可能存在具有分化和更新潜能的祖细胞,脊髓损伤后这些细胞被激活,在功能恢复中可能发挥着重要的作用。     

Dose-dependent neuroprotective effects of melatonin on experimental spinal cord injury in rats

BACKGROUND: This report examines the dose-dependent effects of melatonin on early lipid peroxidation levels, ultrastructural changes, and neurological function in experimental spinal cord injury (SCI) by comparing them with therapeutic levels of methylprednisone in rats. METHODS: SCI was performed by an aneurysm clip placed extradurally at the level of T10. Rats were randomly divided into six groups of 10 rats each. Group 1 (sham) received only laminectomy; group 2 (control) received SCI; group 3 (placebo) received SCI and physiological saline; group 4 received methylprednisone (30 mg/kg); groups 5 and 6 received melatonin at doses of 50 or 100 mg/kg, respectively, after SCI. Rats were neurologically tested 24 hours after trauma. Spinal cord samples were harvested for both lipid peroxidation levels and ultrastructural histopathological evaluation. RESULTS: Neurological scores of rats were not different in SCI groups. Lipid peroxidation levels are significantly restricted only in methylprednisone group at 24 hours. Melatonin-treated groups showed more ultrastructural improvement on electron microscope studies when compared with methylprednisone group. However, the therapeutic effects of melatonin were mainly observed on white matter of spinal cord in ultrastructural investigation. There was significant difference between melatonin dose groups increasing with dose. CONCLUSIONS: Results showed that melatonin has no significant dose-dependent effects on early lipid peroxidation bur rather some neuroprotective effects on both axons and myelin sheaths of white matter in ultrastructural observations when compared with methylprednisone. These effects significantly augmented with dose increase.     

Honokiol exerts protective effects on neural myelin sheaths after compressed spinal cord injury by inhibiting oligodendrocyte apoptosis through regulation of ER-mitochondrial interactions

ObjectiveTo investigate the effect of honokiol on demyelination after compressed spinal cord injury (CSCI) and it''s possible mechanism.DesignAnimal experiment study.SettingInstitute of Neuroscience of Chongqing Medical University.InterventionsTotal of 69 Sprague–Dawley (SD) rats were randomly divided into 3 groups: sham group (n=15), honokiol group (n=27) and vehicle group (n=27). After established CSCI model by a custom-made compressor successfully, the rats of sham group were subjected to the limited laminectomy without compression; the rats of honokiol group were subjected to CSCI surgery and intraperitoneal injection of 20 mg/kg honokiol; the rats of vehicle group were subjected to CSCI surgery and intraperitoneal injection of an equivalent volume of saline.Outcome measures: The locomotor function of each group was assessed using the Basso, Beattie and Bresnahan (BBB) rating scale. The pathological changes of myelinated nerve fibers of spinal cord in 3 groups were detected by osmic acid staining and transmission electron microcopy (TME). Immunofluorescence and Western blot were used to research the experessions of active caspase-3, caspase-12, cytochrome C and myelin basic protein (MBP) respectively.ResultsIn the vehicle group, the rats became paralyzed and spastic after injury, and the myelin sheath became swollen and broken down along with decreased number of myelinated nerve fibers. Western blot analysis manifested that active caspase-3, caspase-12 and cytochrome C began to increase 1 d after injury while the expression of MBP decreased gradually. After intervened with honokiol for 6 days, compared with the vehicle group, the locomotor function and the pathomorphological changes of myelin sheath of the CSCD rats were improved with obviously decreased expression of active caspase-3, caspase-12 and cytochrome C.ConclusionsHonokiol may improve locomotor function and protect neural myelin sheat from demyelination via prevention oligodendrocytes (OLs) apoptosis through mediate endoplasmic reticulum (ER)-mitochondria pathway after CSCI.     

腰椎间盘突出症患者髓核组织中受体相互作用的丝氨酸苏氨酸激酶1表达和临床意义

目的:探讨腰椎间盘突出症(lumbar disc herniation,LDH)患者髓核组织中受体相互作用的丝氨酸苏氨酸激酶1(receptor-interacting protein serine-threonine kinases 1,RIPK1)表达和临床意义.方法:选取2016年1月至2018年1月治疗40例L...     

自噬蛋白p62在急性脊髓损伤大鼠脊髓组织中的表达

目的观察p62在早期急性脊髓损伤(SCI)模型大鼠脊髓组织中的表达变化,探讨p62在急性SCI的作用。方法将SD大鼠随机分为假手术组和造模后1、3、7、14 d组,每组6只。采用高空重物坠落击打方法造成大鼠SCI。采用Basso、Beattie、Bresnahan(BBB)评分法评估大鼠神经功能,取损伤的脊髓组织进行HE染色,观察病理学改变。通过实时荧光定量PCR、蛋白质印迹法和免疫组织化学方法检测急性SCI后大鼠脊髓组织中p62的表达变化。结果造模后1、3、7、14 d组BBB评分分别为(2.00±0.89)分、(4.67±1.03)分、(7.83±0.75)分、(14.50±1.05)分,均低于假手术组(21.00分),差异有统计学意义(P 0.05)。造模后1、3、7、14 d组损伤的脊髓组织神经元和白质髓鞘发生肿胀,随时间的延长逐渐出现变性和坏死。造模后1、3、7、14 d组p62表达逐渐增加,并呈持续增长趋势。结论 p62在大鼠发生急性SCI后表达持续增加,提示p62在急性SCI后发挥一定作用。     

Post-traumatic moderate systemic hyperthermia worsens behavioural outcome after spinal cord injury in the rat

STUDY DESIGN: A standardized rat model of compression spinal cord injury (SCI) was used to test the effect of transient systemic hyperthermia on long-term behavioural and morphometric outcomes. OBJECTIVE: To determine the effect of hyperthermia on the development of spinal cord lesion after SCI.Setting:Institute of Neurobiology, Slovak Republic. METHODS: Male Wistar rats (n=30) weighing between 300 and 330 g were used in the study. After incomplete spinal injury performed by balloon compression at the Th8-Th9 spinal level, rats were randomly divided into two groups. Rats in the treatment group were maintained hyperthermic for 3 h (rectal temperature at 40.5+/-0.5 degrees C), immediately after SCI; rats from the control group received exactly the same procedure except that their rectal temperature was maintained at 37+/-0.5 degrees C. RESULTS: The 3 h of post-traumatic hyperthermic treatment worsened behavioural outcome after SCI. Morphometric analysis showed that hyperthermia had a deleterious effect on white and grey matter, but the results did not reach statistical significance. CONCLUSION: These results indicate that systemic hyperthermia exacerbates secondary processes in the lesion and significantly worsens behavioural outcome after traumatic SCI in the rat.     

Cotransplant of neural stem cells and NT-3 gene modified Schwann cells promote the recovery of transected spinal cord injury

STUDY DESIGN: An animal model of transected spinal cord injury (SCI) was used to test the hypothesis that cografted neural stem cells (NSCs) and NT-3-SCs promote morphologic and functional recoveries of injured spinal cord. OBJECTIVE: To explore whether cotransplant of NSCs and NT-3-SCs could promote the injured spinal cord repair. SETTING: Zhongshan Medical College, Sun Yat-sen University, PR China. METHODS: Female Sprague-Dawley (SD) rats weighing on 200-220 g were used to prepare SCI models. The spinal cord was transected between T(9) and T(10), then NSCs, SCs+NSCs, LacZ-SCs+NSCs, or NT-3-SCs+NSCs were grafted into the transected site. RESULTS: (1) Part of NSCs could differentiate to neuron-like cells in the transected site and the percentage of differentiation was NT-3-SCs+NSCs group>SCs+NSCs group>NSCs group. (2) In the grafted groups, there were 5-HT, CGRP, and SP positive nerve fibres within the transected site. Some fluorogold (FG)-labeled cells were found in the spinal cord rostral to the transected site, the red nuclei and the inner pyramidal layer of sensorimotor cortex. (3) The cells grafted could enhance the injured neurons survival in inner pyramidal layer of sensorimotor cortex, red nuclei of midbrain, and Clark's nuclei of spinal cord's L1 segment, could decrease the latency and increase the amplitude of cortical somatosensory evoked potential (CSEP) and cortical motor evoked potential (CMEP), and could promote partly structural and functional recovery of the SCI rats. CONCLUSION: These results demonstrate that cografted NT-3-SCs and NSCs is a potential therapy for SCI. SPONSORSHIP: This research was supported by Chinese National Key Project for Basic Research (G1999054009), Chinese National Natural Science Foundation (30270700) and Social Developmental Foundation of Guangdong Province (2003C33808) to YS Zeng; Natural Science Foundation of Guangdong Province (04300468) and Medical Science Research Grant of Guangdong Province (A2004081) to JS Guo.     

周围神经移植修复大鼠陈旧性脊髓损伤的实验研究

目的：探讨利用自体周围神经组织游离移植修复大鼠陈旧性脊髓损伤病理机制。方法：利用改良Allen撞击方法建立脊髓打击损伤模型后，将大鼠分为2组，各20只。神经移植组切取后肢腓肠神经，利用显微外科技术去除神经外膜，将其修剪成小段，游离移植于脊髓损伤处，对照组不作处理。分别于术后4、12周，在光镜下观察脊髓损伤段及移植周围神经再生情况，并应用辣根过氧化物酶神经逆行示踪技术进行脊髓神经束的再生评价。分3个时点（1、2、3个月）观察大鼠后肢运动功能恢复情况。结果：对照组脊髓变性，可见瘢痕和空洞，移植组术后12周，损伤区脊髓与周围神经融合良好，可见再生轴突，跨越损伤段脊髓，周围神经无变性。12周时脊髓神经束的再生评价结果提示：神经移植组优于对照组．移植组大鼠后肢运动功能明显恢复。结论：周围神经组织游离移植修复大鼠陈旧性脊髓损伤后，存活良好并可促进大鼠脊髓结构和功能的恢复。