Rh-bFGF用于临床治疗脊髓半离断继发脑病变的实验性研究

目的：探讨ｂＦＧＦ是否对脊髓损伤后的大脑皮质运动神经元具有保护作用。方法：用Ｎｉｓｓｌ染色和ＧＦＡＰ免疫色对脊髓半离断后的大脑皮质运动区神经元和胶质细胞进行了定量和定性研究。结果：１ Ｎｉｓｓａｌ染色显示：（１）在对照组大鼠额皮质内神经元和神经胶质细胞未见异常；（２）在损伤组大鼠额皮质内见到大量神经元变性和胶质细胞增生明显以及胶质细胞嗜神经元现象：（３）在治疗组大鼠额皮质区内未见嗜神经元现象，但胶     

微囊化兔坐骨神经组织细胞移植对脊髓损伤后大鼠GDNF表达的影响

目的探讨微囊化兔坐骨神经组织细胞移植对脊髓半横断损伤后大鼠胶质细胞源性神经营养因子（GDNF）的表达影响。方法成年SD大鼠80只随机分为4组,微囊组（n=25）、细胞组（n=25）、单损组（n=25）、正常组（n=5）。术前制备兔坐骨神经细胞混悬液以及将其微囊化,微囊组、细胞组和单损组大鼠在脊髓半横断伤后,立即在损伤处分别植入10μl微囊化坐骨神经组织细胞1、0μl坐骨神经组织细胞以及10μl生理盐水。于术后2 d7、d1、4 d、21 d2、8 d（每个时相取5只大鼠）取出损伤部位脊髓组织,正常组（每个时相取1只大鼠）则取相应节段脊髓。组织石蜡包埋后切片,行免疫组织化学染色观察GDNF的表达变化。结果 GDNF阳性染色主要见于神经元细胞及胶质细胞的胞浆内。大鼠脊髓损伤后上述细胞2 d后表达开始上升2,1 d达到最高。微囊组与单损组、细胞组比较差异有显著性（P〈0.05）。结论微囊化兔坐骨神经组织细胞移植于大鼠损伤脊髓后,可以抑制炎症反应,促进GDNF的表达,有利于大鼠运动功能恢复。     

神经干细胞移植修复大鼠脊髓半切伤的研究

目的：观察神经干细胞移植修复脊髓半切伤的疗效并探讨移植最佳时机。方法：制备大鼠T13-L1脊髓半切伤模型，取胎龄13、5d胎鼠大脑组织，体外分离、培养、诱导神经干细胞，并采用免疫细胞化学技术分别检测NSC（neural stemcell）特征性标志Nestin（巢蛋白）表达和用血清诱导分化为大量神经元NSE（neuron specific enolas）和神经胶质细胞GFAP（glial fibrillary acidic protein）表达。用明胶海绵吸附BrdU（5-溴脱氧尿嘧啶）标记好的神经干细胞悬液移植到脊髓半横断处，移植时间选择损伤后立即移植、损伤后第9、14d。观察移植后的大鼠行为的变化，通过CBS（combine behavioral score）评分和爬网格实验评价大鼠的运动功能恢复情况，并进行免疫组化鉴定，光学显微镜观察移植神经干细胞的存活和迁移。结果：在上述条件下培养及传代的细胞不断分裂增殖，形成悬浮生长的呈Nestin阳性的神经球；用血清诱导分化为大量表达NSE阳性的神经元和GFAP阳性的神经胶质细胞。与对照组相比，神经干细胞移植组明显修复了损伤结构，改善了下肢的功能，尤其是第9d移植组。结论：神经干细胞移植促进了脊髓损伤后神经结构和功能的恢复，是治疗脊髓半切伤一种有效方案，考虑综合因素移植干细胞的最佳时机应选损伤后9d左右。     

转基因小鼠脊髓损伤后室管膜细胞的时空动态变化北大核心

背景:成年哺乳动物脊髓室管膜细胞损伤后表现出干/祖细胞特性。目的:利用Nestin和Foxj1转基因小鼠标记室管膜细胞,以便追踪室管膜细胞及其子代在成年小鼠脊髓损伤后的增殖分化命运。方法:对转基因小鼠T_(8)脊髓节段完全切除1 mm脊髓组织,术后1-7 d连续腹腔注射BrdU动态观察室管膜细胞,在脊髓损伤后不同时间点(3,7,14,28,56 d)借助BrdU,GFAP,Tuj1,NeuN免疫荧光染色,观察损伤区边缘室管膜细胞的遗传命运谱。结果与结论:①未损伤脊髓中,Nestin阳性的室管膜细胞处于静止状态;脊髓损伤后室管膜细胞被激活,第3天时在损伤区周围大量增殖;②在损伤后第28天,约3.3%Nestin阳性的室管膜细胞表达神经元标记物Tuj1;③在损伤后第56天,约25.7%Nestin阳性的室管膜细胞分化为星形胶质细胞并构成胶质瘢痕的核心,参与胶质瘢痕的形成;④通过检测室管膜细胞在脊髓损伤后的时空动态变化、增殖和分化特征,为理解脊髓损伤的病理过程提供理论依据,为脊髓损伤修复提供新的思路。     

大鼠脊髓损伤后NGF及其受体TrkA在运动神经元及神经胶质细胞表达的变化

为探讨脊髓损伤后运动神经元及神经胶质细胞内神经生长因子(NGF)及其高亲和力受体(TrkA)表达的变化,用改良Allen重击法损伤SCI组动物T12脊髓,按伤后存活时间再将动物分为脊髓损1 d组、2 d组和5 d组。各组动物的脊髓切片经ABC法免疫组织化学染色,用光镜观察TrkA及NGF在脊髓前角运动神经元表达的变化和胶质纤维酸性蛋白(GFAP)及NGF免疫反应阳性胶质细胞的反应性增生程度,并进行图像分析。结果显示:脊髓损伤后前角运动神经元TrkA及NGF的表达随脊髓损伤后动物存活时间的延长逐渐上调;脊髓白质和灰质内尤其是皮质脊髓束内GFAP及NGF阳性胶质细胞明显增生;与此同时,室管膜细胞内亦可见明显的NGF免疫反应产物。上述结果表明,脊髓损伤可刺激脊髓前角运动神经元表达TrkA及NGF,通过自分泌维持受损神经元的存活;损伤部位反应性增生的胶质细胞亦可产生NGF,通过旁分泌作用于脊髓前角运动神经元或皮质脊髓束的轴突末梢,以维持运动神经元的存活及促进皮质脊髓束的再生;适时补充外源性神经营养素或改变损伤局部的微环境将有利于受损脊髓的修复和再生。     

大鼠脊髓挤压伤后小胶质细胞Toll样受体4表达的变化

目的探讨脊髓挤压伤后各时间点小胶质细胞Toll样受体4(TLR4)的表达变化及其与损伤面积和免疫球蛋白G渗出范围的关系。方法 48只成年雄性SD大鼠建立T8节段脊髓挤压伤模型,随机分为6组,每组8只;假手术对照组及挤压伤组动物在手术后0h、3h、24h、72h和7d用4%多聚甲醛灌注固定,取以挤压点为中心的2cm脊髓,冷冻切片后进行HE染色和免疫荧光染色,分别观察损伤面积的变化,TLR4表达和TLR4阳性小胶质细胞的分布,以及与血浆免疫球蛋白G(IgG)渗出范围的比较,并用IPP6.0软件计算各组的阳性数目。结果脊髓损伤后TLR4主要表达在小胶质细胞,在3～24h之间开始表达,伤后在72h达到高峰,7d时已经显著下降。阳性小胶质细胞的分布与IgG渗出范围一致。结论大鼠脊髓挤压伤模型中,表达在脊髓小胶质细胞上的TLR4可在脊髓继发性损伤中发挥重要作用,并与血脊髓屏障开放有关。     

GDNF及HSV—GDNF对坐骨神经损伤大鼠脊髓运动神经元Bcl—2表达的影响

目的：观察胶质细胞源性神经营养因子（GDNF）及单纯疱疹病毒（HSV）载体介导的GDNF（HSV－GDNF）对坐骨神经损伤大鼠脊髓运动神经元了Bcl-2表达的影响。方法：分别取坐骨神经损伤后4d、7d和14d大鼠（）分成对照组、GDNF组和HSV－GDNF组）的腰段脊髓）L4－6）,行石蜡包埋,切片、;用抗Bcl-2抗血清进行免疫组织化学染色,观察Bcl-2免疫反应（Bcl-2－IR）神经元数目,并在图像分析仪Bcl-2－IR阳性神经元作光密度的色谱分析。结果：1．坐骨神经损伤后4d、7d,GDNF组和HSV－GDNF组损伤侧脊髓运动神经Bcl-2－IR阳性神经元的数量和平均光密度均明显高于对照组损伤测,2．坐骨神经损伤后14d时,对照组、GDNF组和HSV－GDNF组损伤侧脊髓运动神经元对Bcl-2的表达已无明显差别。结论GDNF与HSV－GDNF能够增强坐骨神经扣内务 大鼠脊髓运动神经元Bcl-2的表达,减少神经元的退化死亡。     

大鼠脊髓发育及损伤后NIDD mRNA表达的实验研究

目的：探讨在大鼠发育过程中及急性脊髓损伤后脊髓组织中NIDD （nNOS-interacting DHHC domain-containing protein with dendritic mRNA）mRNA的表达变化及意义。方法：采用改良Allen＇s打击法，咬除T8-10椎板后，造成大鼠脊髓损伤模型，致伤量为10×10g·cm；借助实时荧光定量PCR、原位杂交与免疫荧光结合的方法，定量、定位研究发育过程中及脊髓损伤后早期大鼠脊髓组织中NIDD mRNA与nNOS mRNA表达的时间和空间分布特征。结果：大鼠发育过程中，胚胎16d的大鼠脊髓中可见NIDD mRNA的高表达，在生后1d，与nNOS共表达于尚未分化成熟的前角，在白质也见NIDD的阳性信号。成年后呈低表达；nNOS mRNA于生后1～3d出现表达高峰；脊髓损伤后NIDD mRNA表达明显增多，在8h到达高峰，分布于脊髓前角、中间带、中央管周围及后角nNOS阳性的神经元，7d恢复至正常水平；nNOS mRNA在损伤后8h达到高峰，1d降低至正常水平。而且，在脊髓损伤后NIDD mRNA与nNOS mRNA二者表达呈正相关。结论：胎鼠脊髓中，NIDD高表达于nNOS阳性细胞，提示其在脊髓组织的发育成熟过程中的作用可能与nNOS相关。脊髓损伤后脊髓组织中NIDD与nNOS表达增多，提示在脊髓损伤的病理过程中，NIDD可能通过调节nNOS的细胞亚定位及活性而发挥一定的生物学作用。     

脊髓全横断模型大鼠损伤区白细胞介素17的表达

背景：现阶段,针对已知的炎性递质的干预措施对于减轻脊髓继发损伤的效果局限。白细胞介素17是重要的促炎性细胞因子,在中枢神经系统疾病发病机制中的作用正逐渐受到关注。 目的：观察急性脊髓损伤模型大鼠白细胞介素17 mRNA和蛋白表达的变化规律。 方法：健康雄性SD大鼠随机分为2组：模型组制作大鼠脊髓完全横断模型,假手术组仅剪开硬脊膜而不伤及脊髓实质。开放后测定肢运动功能评分观察急性脊髓损伤对大鼠运动功能的影响,苏木精-伊红染色观察脊髓损伤后不同时间点组织病理学改变,实时荧光定量PCR、Western blot分别检测各组大鼠脊髓损伤后不同时间点白细胞介素17 mRNA和蛋白水平表达变化。 结果与结论：开放后肢运动功能评分结果：假手术组大鼠BBB评分均为20-21分,脊髓损伤1,2 d大鼠BBB评分均为0分,损伤后7 d BBB评分为0-3分(P < 0.05)。苏木精-伊红染色结果：与假手术组相比,脊髓损伤6 h后,炎性细胞浸润,神经元和胶质细胞肿胀,神经元突起减少;脊髓损伤12 h后,灰质、白质组织结构疏松、空泡化;脊髓损伤后7 d,胶质细胞增生,组织纤维化明显。RT-qPCR结果显示：白细胞介素17 mNA于脊髓损伤后3 h出现,并于6 h表达出现高峰(P < 0.01),随后表达减少,7 d后表达接近假手术组水平。Western blot结果显示：脊髓损伤6 h后,白细胞介素17表达开始升高,并于损伤后12 h出现高峰(P < 0.05),随后表达减少,至伤后7 d表达接近假手术组水平。结果可见脊髓损伤12 h后组织损伤表现最严重,并与白细胞介素17表达改变存在时间的一致性,推断白细胞介素17可能参与了脊髓继发性炎症反应过程。 中国组织工程研究杂志出版内容重点：肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程全文链接：     

巨噬细胞迁移抑制因子在小鼠脊髓损伤后的表达研究

目的探讨巨噬细胞迁移抑制因子(MIF)在小鼠脊髓损伤后的修复作用。方法选择C57BL/6小鼠制作重物砸伤的脊髓损伤模型,分为手术组和假手术对照组,损伤节段为T9~T10;用免疫组织化学法显示MIF在损伤急性期(术后72 h)的表达改变。用RT-PCR显示MIF与RhoA的mRNA水平改变;用免疫荧光双标显示小胶质细胞表达MIF和RhoA的情况。结果重物坠落致脊髓损伤后72 h,MIF在损伤段脊髓中蛋白表达量增加;同时MIF的mRNA水平升高,且伴随RhoA的mRNA水平升高,手术组和假手术组之间的差异有统计学意义(P0.05)。结论重物坠落致脊髓损伤后的急性期,损伤局部活化的小胶质细胞中MIF表达增加;少突胶质和星形胶质样细胞中有MIF累积,神经元中MIF的水平变化不显著。同时,MIF的mRNA水平也出现上调,与RhoA的mRNA上调在时空上有一致性,提示MIF可能调节损伤局部微环境参与轴突再生抑制。     

Acute and chronic changes in aquaporin 4 expression after spinal cord injury

The effect of spinal cord injury (SCI) on the expression levels and distribution of water channel aquaporin 4 (AQP4) has not been studied. We have found AQP4 in gray and white matter astrocytes in both uninjured and injured rat spinal cords. AQP4 was detected in astrocytic processes that were tightly surrounding neurons and blood vessels, but more robustly in glia limitans externa and interna, which were forming an interface between spinal cord parenchyma and cerebrospinal fluid (CSF). Such spatial distribution of AQP4 suggests a critical role that astrocytes expressing AQP4 play in the transport of water from blood/CSF to spinal cord parenchyma and vice versa. SCI induced biphasic changes in astrocytic AQP4 levels, including its early down-regulation and subsequent persistent up-regulation. However, changes in AQP4 expression did not correlate well with the onset and magnitude of astrocytic activation, when measured as changes in GFAP expression levels. It appears that reactive astrocytes began expressing increased levels of AQP4 after migrating to the wound area (thoracic region) two weeks after SCI, and AQP4 remained significantly elevated for months after SCI. We also showed that increased levels of AQP4 spread away from the lesion site to cervical and lumbar segments, but only in chronically injured spinal cords. Although overall AQP4 expression levels increased in chronically-injured spinal cords, AQP4 immunolabeling in astrocytic processes forming glia limitans externa was decreased, which may indicate impaired water transport through glia limitans externa. Finally, we also showed that SCI-induced changes in AQP4 protein levels correlate, both temporally and spatially, with persistent increases in water content in acutely and chronically injured spinal cords. Although correlative, this finding suggests a possible link between AQP4 and impaired water transport/edema/syringomyelia in contused spinal cords.     

Upregulation of phospholipase D1 in the spinal cords of rats with clip compression injury

This study examined phospholipase D 1 (PLD1) expression in the central nervous system following clip compression spinal cord injury (SCI) in Sprague-Dawley rats. After inducing SCI with a vascular clip, the expression of PLD1 in the affected spinal cord was analyzed by Western blot and immunohistochemistry. Western blot analysis showed that the expression of PLD1 gradually increased in the spinal cord on days 0.5, 1, 2, and 4 post injury. Immunohistochemistry showed that some cells, including neurons, astrocytes, and some inflammatory cells, were positive for PLD1 in the lesions at days 1 and 2 post injury. At day 4, the number of PLD1-positive cells in SCI lesions increased, largely matching the increases in ED1-positive macrophages and glial fibrillary acidic protein-positive astrocytes. At this time, macrophages expressed proliferating cell nuclear antigen in addition to PLD1. These results suggest that PLD1 expression is increased in injured spinal cords, and might be involved in the activation and proliferation of macrophages and astrocytes in SCI.     

脐带间充质干细胞移植对脊髓损伤小鼠运动功能的修复和镇痛作用

目的：探讨人脐带间充质干细胞（ hUC-MSCs）移植缓解脊髓损伤神经病理性痛,并促进功能恢复的效果及 其与脊髓损伤小鼠胶质细胞活化及炎症因子水平的调控关系。方法：建立ICR 小鼠脊髓损伤模型,同时构建慢病毒 载体介导绿色荧光蛋白（ GFP）标记体外培养的 hUC-MSCs ;将模型小鼠分为模型组和治疗组,治疗组于脊髓损 伤1 周后采用局部注射 hUC-MSCs 移植到脊髓中,每周进行运动功能（ BBB）评分及机械性痛觉过敏检测,持续8 周后行组织学评价与炎症因子检测。结果：治疗组脊髓组织中 GFP 荧光有表达。BBB检测结果显示,治疗组和模 型组小鼠随时间延长运动功能均逐渐恢复,其中治疗组运动功能恢复速度要显著快于模型组;机械触诱发痛检测显 示,小鼠脊髓损伤后痛阈值降低,随着时间延长痛阈值逐渐升高。同一个时间点治疗组的痛阈值显著高于模型组。 与模型组相比,治疗组小鼠脊髓组织的白细胞介素-6（ IL-6）、肿瘤坏死因子-α（ TNF-α）表达下降,胶质细胞源 性神经营养因子（ GDNF）表达升高,同时脊髓组织巨噬细胞激活抗原1（ ED1/CD68） 荧光表达显著降低。结论： 脊髓损伤小鼠中hUC-MSCs 移植可能通过降低炎症因子 IL-6 和TNF-α 的分泌,提高 GDNF 的表达水平来促进受损 脊髓组织的修复,并发挥镇痛效应。     

微囊化兔雪旺细胞移植对大鼠损伤脊髓胶质纤维酸性蛋白表达的影响

目的:观察大鼠脊髓损伤后及进行微囊化兔雪旺细胞移植后胶质纤维酸性蛋白(GFAP)表达的变化.方法: 130只成年SD大鼠随机分为微囊组、细胞悬液组、损伤对照组和正常对照组4组,术后3、 7、 14及28d,冰冻切片行免疫组织化学显色观察GFAP表达的变化.结果:大鼠脊髓损伤后3～14d, GFAP阳性细胞数及平均光密度均增加;至第28天时则减少,但仍高于正常组.其中阳性细胞数和平均光密度在第7天开始,微囊组与细胞悬液组、损伤组比较均有明显降低.结论: 微囊化异种雪旺细胞移植能抑制损伤脊髓GFAP的表达,减轻由反应性胶质化所形成的胶质瘢痕.     

Endogenous neural stem cells in central canal of adult rats acquired limited ability to differentiate into neurons following mild spinal cord injury

Endogenous neural stem cells in central canal of adult mammalian spinal cord exhibit stem cell properties following injury. In the present study, the endogenous neural stem cells were labeled with Dil to track the differentiation of cells after mild spinal cord injury (SCI). Compared with 1 and 14 days post mild injury, the number of endogenous neural stem cells significantly increased at the injured site of spinal cord on 3 and 7 days post-injury. Dil-labeled βIII-tublin and GFAP expressing cells could be detected on 7 days post-injury, which indicated that the endogenous neural stem cells in central canal of spinal cord differentiated into different type of neural cells, but there were more differentiated astrocytes than the neurons after injury. Furthermore, after injury the expression of inhibitory Notch1 and Hes1 mRNA began to increase at 6 hours and was evident at 12 and 24 hours, which maintained high levels up to 7 days post-injury. These results indicated that a mild SCI in rat is sufficient to induce endogenous neural stem cells proliferation and differentiation. However, the ability to differentiate into neurons is limited, which may be, at least in part, due to high expression of inhibitory Notch1 and Hes1 genes after injury.     

p27kip1和Skp2在大鼠坐骨神经夹伤后脊髓中的表达变化

目的:研究p27~(kip1)和Skp2在正常和坐骨神经夹伤后大鼠脊髓中的表达变化。方法:Westem印迹法,免疫组织化学,免疫荧光双标。结果:Western印迹结果显示坐骨神经夹伤后,脊髓中p27~(kip1)表达下降后又有所恢复,并且p27~(kip1)和Skp2在脊髓中的表达变化呈负相关。免疫组织化学及免疫荧光双标显示,p27~(kip1)和Skp2在正常和损伤后的脊髓神经元和胶质细胞中都有表达。坐骨神经夹伤后p27~(kip1)和Skp2在脊髓腹角阳性细胞数目变化呈负相关。结论:坐骨神经损伤后p27~(kip1)。和Skp2在脊髓腹角神经元及其周围的胶质细胞表达变化相关,对研究脊髓损伤和修复的分子机制有重要意义。     

龟板对脊髓损伤后大鼠功能和骨形态发生蛋白4表达的影响

目的　观察龟板对大鼠损伤脊髓骨形态发生蛋白 4 (BMP4 )表达和后肢功能恢复的影响。方法　应用改良Allen脊髓损伤模型 ,于术后 1、7、14、2 1、2 8d分别对大鼠进行Tarlov评分和斜板试验检查后肢功能。应用免疫组织化学技术检测BMP4的表达 ,观察龟板对脊髓损伤后BMP4的影响。结果　脊髓损伤后第 1d ,在两组受损伤脊髓灰质中都可见到BMP4的表达。第 14d时达到高峰 ,龟板组为 37 2 4± 5 73,损伤组 2 1 4 8± 6 83(P <0 0 5 )。龟板组可使损伤的脊髓BMP4持续高表达至术后第 2 8d ,而损伤组仅持续表达至术后 2 1d。增加的BMP4阳性细胞数与神经功能的改善平行。结论　龟板可减轻神经损伤症状和促进脊髓损伤后BMP4表达     

脊髓损伤后水通道蛋白-4的时程变化

探讨脊髓损伤后水通道蛋白-4及其mRNA的变化规律,应用改良Allen脊髓损伤的模型,于术后1、3、7和14 d取脊髓组织,采用免疫组织化学和原位杂交技术检测AQP-4的表达。结果表明,AQP-4及其mRNA表达丰富的部位主要集中在损伤脊髓的后索、前索和后角,以小胶质细胞和少突胶质细胞为主。AQP-4及其mRNA表达在脊髓损伤后1 d开始增加,在脊髓损伤后3 d达到高峰。随后下降,对应的病理改变为细胞内水肿。本研究结果提示:胶质细胞AQP-4表达增强与早期损伤性脊髓水肿密切相关,它可能是形成早期细胞内水肿的重要因素之一。     

Raman spectroscopic investigation of spinal cord injury in a rat model

Raman spectroscopy was used to study temporal molecular changes associated with spinal cord injury (SCI) in a rat model. Raman spectra of saline-perfused, injured, and healthy rat spinal cords were obtained and compared. Two injury models, a lateral hemisection and a moderate contusion were investigated. The net fluorescence and the Raman spectra showed clear differences between the injured and healthy spinal cords. Based on extensive histological and biochemical characterization of SCI available in the literature, these differences were hypothesized to be due to cell death, demyelination, and changes in the extracellular matrix composition, such as increased expression of proteoglycans and hyaluronic acid, at the site of injury where the glial scar forms. Further, analysis of difference spectra indicated the presence of carbonyl containing compounds, hypothesized to be products of lipid peroxidation and acid catalyzed hydrolysis of glycosaminoglycan moieties. These results compared well with in vitro experiments conducted on chondroitin sulfate sugars. Since the glial scar is thought to be a potent biochemical barrier to nerve regeneration, this observation suggests the possibility of using near infrared Raman spectroscopy to study injury progression and explore potential treatments ex vivo, and ultimately monitor potential remedial treatments within the spinal cord in vivo.