大鼠脊髓损伤继发骨质疏松生物力学性质实验研究

研究了正常大鼠骨和脊髓损伤所致大鼠骨质疏松骨的生物力学性质。选用280g～320g4月～5月龄Wistar雄性大鼠70只，随机分为0周空白对照组10只，3周对照组10只，7周对照组10只，11周对照组10只，三周实验组10只，7周实验组10只，11周实验组10只，0周空白组于0周处死，解剖取大鼠股骨、胫骨、肱骨，以生理盐水浸温的纱布包裹，置-20℃冰箱内保存备用。对3周、7周、11周对照组大鼠以咬骨钳将其椎板咬开，不破坏硬膜和脊髓，进行饲养。对3周、7周、11周实验组大鼠人为造成脊髓损伤后饲养，复制骨质疏松模型。分别于3周、7周、11周处死对照组和实验组大鼠。取0周空白组和11周实验组胫骨制作脱钙切片进行骨组织形态观察。 取大鼠股骨进行弯曲实验，取肱骨进行拉伸实验，取胫骨进行冲击实验。取0周空白组、3周实验组、7周实验组、11周实验组大鼠股骨进行应力松弛、蠕变实验，得出了各组大鼠肱骨拉伸力学性能指标、各组大鼠股骨弯曲力学性能指标，各组大鼠胫骨冲击性能指标和大鼠股骨0周，3周、7周、11周对照组大鼠股骨应力松驰、蠕变数据及曲线。实验结果表明，模型组和对照组的各项力学性能指标显著低于0周空白组（P〈0．05）。对脊髓损伤导致大鼠骨质疏松对骨力学性能指标的影响进行分析讨论。     

脊髓损伤继发骨质疏松动物模型骨力学性质实验研究

目的 研究正常大鼠骨和脊髓损伤所致大鼠骨质疏松骨力学性质,为临床提供生物力学参数.方法 选用280～320 g,4～5月龄wistar雄性大鼠77只,随机分为0周空白对照组11只,3周对照组11只,7周对照组11只,11周对照组11只,三周实验组11只,7周实验组11只,11周实验组11只.0周空白组于0周处死,解剖取大鼠股骨、胫骨、肱骨,以生理盐水浸温的纱布包裹,置-20℃冰箱内保存备用.对3、7、11周对照组大鼠以咬骨钳将其椎板咬开,不破坏硬膜和脊髓,人为造成脊髓损伤后饲养,复制骨质疏松模型.分别于3、7、11周处死对照组和实验组大鼠.取大鼠股骨进行压缩实验,取肱骨进行剪切实验,取胫骨进行扭转实验.结果 得出了各组大鼠股骨压缩力学性能指标、肱骨剪切力学性能指标和胫骨扭转力学性能指标.结论 实验组和对照组的各项力学性能指标显著低于0周空白组(P＜0.05).     

脊髓损伤继发骨质疏松动物模型骨压缩应力松弛蠕变测试

研究正常大鼠骨和脊髓损伤所致大鼠骨质疏松骨的力学性质,为临床提供粘弹性力学参数.选用280～320 g 4～5月龄wistar雄性大鼠44只,随机分为0周空白对照组11只,3周实验组11只,7周实验组11只,11周实验组11只,0周空白组于0周处死,解剖取大鼠股骨,以生理盐水浸湿的纱布包裹,置-20℃冰箱内保存备用.对3、7、11周实验组大鼠人为造成脊髓损伤后饲养,复制骨质疏松模型.分别于3、7、11周处死实验组大鼠,解剖取大鼠股骨.对0周空白组、3周实验组、7周实验组、11周实验组大鼠股骨进行压缩应力松弛、蠕变实验.结果得出了各组大鼠股骨压缩应力松 弛函数、蠕变函数及曲线.实验组的各项力学性能指标显著低于0周空白组(P＜0.05).     

大鼠脊髓损伤及继发损伤时脊髓诱发电位与运动诱发电位的变化

本文采用改良Ａｌｌｅｎ’ｓ法，分别以５０ｇ／ｃｍ和１００ｇ／ｃｍ打击大鼠Ｔ１３～Ｌ１脊髓，造成不同程度的脊髓损伤，分别观察伤后２４小时内的ＳｐＥＰ和ＣＭＥＰ的变化，以了解不同程度损伤对ＳｐＥＰ和ＣＭＥＰ的影响及ＳｐＥＰ、ＣＭＥＰ的变化与脊髓继发性损伤发展过程的关系。结果表明：①两种不同程度的脊髓损伤均可造成大鼠脊髓ＳｐＥＰ，ＣＭＥＰ的明显变化，尤以ＳｐＥＰ变化明显。损伤越重，电位改变越明显．②在脊髓损伤后１～２４小时内，伤后１０分钟ＳｐＥＰ，ＣＭＥＰ波幅却有明显降低，４～８小时进一步降低。两次降低有明显差异。ＳｐＥＰ峰潜伏时延长，以４～８小时显著。表明原发损伤后在受损部位存在继发性损伤，提示阻止继发损伤的时间应早于伤后４小时，并尽可能提前。     

维甲酸致骨质疏松大鼠椎骨压缩、弯曲、扭转、冲击实验研究

研究正常大鼠与维甲酸致骨质疏松大鼠椎骨的力学性质,为临床提供生物力学参数。选用280~360g8、个月龄wistar雄性大鼠88只,随机分为正常对照组44只,骨质疏松模型组44只。对模型组大鼠每日灌服维甲酸(700mg.Kg-1),对2组大鼠饲养14周,以腹主动脉放血法处死大鼠,取大鼠L1-L4椎骨进行扭转、弯曲、冲击实验,取大鼠L4椎骨进行压缩实验。得出了正常对照组和模型组大鼠L4椎骨压缩最大载荷、最大应力、最大位移、最大应变及弹性模量,得出了正常对照组和模型组大鼠L1-L4椎骨三点弯曲最大载荷、最大弯矩、最大应力、弹性模量等数据,得出了正常对照组和模型组大鼠L1-L4椎骨扭转最大扭矩、扭转角、扭转剪应力、冲击实验最大冲击功、冲击韧性指标。模型组各项力学性能指标小于正常对照组(P<0.05)。     

成年大鼠脊髓损伤后血-脊髓屏障通透性变化

为了观察脊髓挤压伤后血-脊髓屏障(BSCB)的通透性变化,本研究选用体重180~200g成年雄性SD大鼠39只,随机分为对照组(n=3)和脊髓损伤组(n=6)。后者又分为伤后0、8、24、72h以及1周、2周等6组,每组6只,再分为A组、B组,每组各3只。脊髓损伤组A组的组织切片行H.E.染色,显微镜下观察脊髓损伤后的形态学变化。对照组和B组动物股静脉注射30g/L伊文思蓝,30min后,以温生理盐水及4%多聚甲醛灌注动物,取出脊髓,行冰冻切片,荧光显微镜下观察。结果观察到,脊髓挤压伤术后72h内,损伤区周围均可见伊文思蓝染色,至1周后损伤区周围未见伊文思蓝染色。本研究结果提示,脊髓损伤72h内可能为有效给药时间窗,1周后给药,药物对脊髓损伤的治疗作用将难以达到治疗目的。     

大鼠脊髓损伤及继发损伤时脊髓诱发电位与运动诱发电位…

本文采用改良Ａｌｌｅｎ＇ｓ法，分别以５０ｇ／ｃｍ和１００ｇ／ｃｍ打击大鼠Ｔ２１３－Ｌ１脊髓，造成不同程度的脊髓损伤，分别观察伤后２４小时内的ＳｐＥＰ和ＣＭＥＰ的变化，以了解不同程度损伤对ＳｐＥＰ和ＣＭＥＰ的影响及ＳｐＥＰ、ＣＭＥＰ的变化与脊髓继发性损伤发展过程的关系。结果表明（１）两种不同程度的脊髓损伤均可造成大鼠脊髓ＳｐＥＰ，ＣＭＥＰ的明显变化，尤以ＳｐＥＰ变化明显。损伤越重，电位改变越明显，（     

大鼠脊髓全横断损伤模型的建立

目前用于脊髓全横断的动物模型,常遗有部分未损脊髓组织,局部脊髓损伤范围很大,尤其是破坏了的血运扩大了继发性变性,造成了复杂的局部病理变化,致使难以分析治疗性脊髓伤区内移植的疗效。因此迫切需要一种还原论式的脊髓横断模型,本实验设计了一种切割辅以吸除的方法,可以在局部造成平均约0.6mm的清洁横断区,同时保存脊髓腹、背动脉及脊髓背静脉的大鼠脊髓横断模型,并用H.E.染色法、神经丝(NF)和胶质纤维酸性蛋白(GFAP)的免疫组织化学方法及生物素化的葡萄糖胺(BDA)的追踪方法检验损伤区及其两侧脊髓的组织反应。     

大鼠脊髓损伤后内皮素含量的变化

将３６例大鼠随机分为６组：对照组、致伤后３０ｍｉｎ、２、４、８和２４ｈ组，以Ａｌｌｅｎ氏法制备中度（５０ｇ·ｃｍ）脊髓损伤（ＳＣＩ）模型，测定各组脊髓组织和血中内皮素（ＥＴ）含量。结果表明，ＳＣＩ后各组伤段脊髓组织ＥＴ明显升高，２ｈ达到高峰，与对照组比较均有显著性差异（Ｐ〈０．００５），血ＥＴ变化与对照组比较无显著性差异（Ｐ〉０．０５）。推测ＥＴ可能通过多种途径参与ＳＣＩ后的继发损伤。     

海人藻酸致大鼠脊髓损伤模型的光镜和电镜研究

用成年Ｗｉｓｔａｒ大鼠７０只，雌雄不拘，通过向腰髓内注射海人藻酸（５μｌ，０．００１ｍｏｌ／Ｌ）建立了脊髓内注射神经毒导致大鼠脊髓损伤的动物模型；一部分向脊髓内注射盐水做为对照．动物按注射后存活２ｈ、６ｈ、１２ｈ、２４ｈ、３ｄ、６ｄ和１４ｄ分组．Ｎｉｓｓｌ染色，电镜观察。注射后２４ｈ内，脊髓腹角神经元出现进行性细胞肿胀，尼氏作皱缩深染，形成许多微细的空泡，胞核浓缩。电镜下观察到内质网、线粒体和高尔基氏体的肿胀和胞质内的空泡和树突的膨胀．注射后３～６ｄ，神经细胞发生明显的退变，细胞质浓缩，尼氏体分解，早期病变的小空泡形成较大的空洞，核偏移。６ｄ后大部分细胞死亡，尚存的脊髓运动神经元明显肿胀，细胞核的边界不清，尼氏体完全消失，电镜下显示细胞器完全被破坏，胞质内的空洞进一步融合形成几个大空洞，细胞核继续浓缩。１４ｄ后注射部位的运动神经元几乎完全消失，胶质细胞明显增生。作为谷氨酸受体激动剂的海人藻酸导致脊髓运动神经元的急性溃变，可作为除撞击、压迫、缺血或横断所致脊髓损伤以外的又一种动物模型，其损伤的病理变化以神经元退变为主，而脊髓的完整性不受破坏，类似于脊髓灰质炎的病变，适用于神经细胞移植的研究。     

Human and rat skeletal muscle adaptations to spinal cord injury.

Results of studies of rodent skeletal muscle plasticity are often extrapolated to humans. However, responses to "disuse" may be species specific, in part because of different inherent properties of anatomically similar muscles. Thus, this study quantified human and rat m. vastus lateralis (VL) fiber adaptations to 11 weeks of spinal cord injury (SCI). The m. VL was taken from 8 young (54 d) male Charles River rats after T-9 laminectomy (n = 4) or sham surgery (n = 4). In addition, the m. VL was biopsied in 7 able-bodied and in 7 SCI humans (31.3 +/- 4.7 years, mean +/- SE). Samples were sectioned and fibers were analyzed for type (I, IIa, IIb/x), cross-sectional area (CSA), succinate dehydrogenase (SDH), alpha-glycerol-phosphate dehydrogenase (GPDH), and actomyosin adenosine triphosphatase (qATPase) activities. Rat fibers had 1.5- to 2-fold greater SDH and GPDH activities while their fibers were 60% the size of those in humans. The most striking differences, however, were the absence of slow fibers in the rat and its four-fold greater proportion of IIb/x fibers (80% vs. 16% of the CSA) compared to humans. SCI decreased SDH activity more in rats whereas atrophy and IIa to IIb/x fiber shift occurred to a greater extent in humans. It is suggested that the rat is a reasonable model for studying the predominant response to SCI, atrophy. However, its high proportion of IIb/x fibers limits evaluation of the mechanical consequences of shifting to "faster" contractile machinery after SCI.     

汉黄芩苷对大鼠脊髓损伤的修复效果

目的 通过观察不同剂量汉黄芩苷对大鼠脊髓损伤后介导的炎症反应的干预情况,探讨汉黄芩苷对脊髓损伤的影响.方法 建立大鼠脊髓横断损伤模型(n=95),随机分成5组:正常组(N)、生理盐水组(NS)、汉黄芩苷低剂量组(WG12.5)、汉黄芩苷中剂量组(WG25)及汉黄芩苷高剂量组(WG50).采用ELISA检测炎性因子肿瘤坏...     

Sex and hormonal variations in the development of at-level allodynia in a rat chronic spinal cord injury model

The development of central neuropathic pain varies among patients with spinal cord injury (SCI). The factors contributing to the development and perpetuation of segmental pain (at-level allodynia) has been the focus of ongoing experiments in our laboratory. One such factor is hormonal status. We have shown previously, using a male rat model of SCI, that a severe contusion injury is necessary for the development of allodynia in trunk regions at and just above the level of a T8 injury. In this study, we examined at-level sensitivity for SCI ovariectomized (ovx) and cycling female rats as well as for SCI males implanted with either a placebo pellet or one that slowly releases 17β-estradiol. The proportion of ovx SCI female rats and placebo-treated SCI males displaying pain-like behaviors to touch/pressure of at-level dermatomes up to 6 weeks post-injury (67% and 75%, respectively) was similar to our previous studies on SCI males (69%). In contrast, significantly fewer cycling SCI female rats and 17β-estradiol treated SCI male rats showed sensitivity to touch at-level (26% and 30%, respectively). These results implicate 17β-estradiol as a potential target that can readily be modulated to prevent segmental pain following SCI.     

一种新型颈椎骨折错位的大鼠原发性脊髓损伤模型

目的　模拟临床建立一种大鼠颈椎骨折错位的原发性脊髓损伤模型。 方法　依据大鼠颈椎解剖特点,自行研制的头侧椎夹固定C3和C4,连接固定于大鼠立体定位架上。尾侧椎夹固定C5和C6并连接到材料试验机,以定速向背侧错位后返回原位,产生C4~5骨折错位和脊髓损伤。按上述方法在8只雄性大鼠C4~5产生骨折错位1.90 mm,错位速度2 mm/s。损伤后立刻行心脏灌注固定,HE染色分析脊髓出血量。 结果 C4~5椎间盘均在C4下终板处断裂,椎间盘破坏的错位位移为(1.00±0.17)mm,最大力为(12.7±5.1)N。肉眼观察到脊髓均有出血,脊髓背侧有两条对称的淤血带,或者色泽较深的出血点;HE染色进一步显示脊髓C4和C5节段的出血主要集中在灰质,而白质有分散的出血点,且背侧较腹侧多,脊髓总出血量为(2.46×10-3±1.26×10-3)ml。 结论 该动物模型可以产生颈椎骨折错位和脊髓损伤,是一种新型的与临床相关的原发性脊髓损伤模型。     

脊髓继发性损伤的纳米微粒药物治疗研究进展

由于脊髓原始损伤后发生的生物学级联反应继续损伤健康的神经细胞会导致继发性脊髓损伤,因此及时减轻级联反应可能会减小脊髓进一步损伤。但是,药物达到有效治疗的运输效率非常受限制。运用结合纳米微粒提高运输效率,降低副作用已经成为医疗应用的主要探索领域。基于纳米微粒的材料属性,它可以通过运输药物到特定的组织治疗脊髓损伤。将纳米技术融入神经损伤和神经疾病的治疗将会带给脊髓损伤的治疗带来新的视野。     

大鼠脊髓损伤后植入人发角蛋白的实验研究

目的：研究人发角蛋白（HHK）在脊髓损伤（SCI）修复中诱导和促进神经元和神经纤维的再生以及HHK在脊髓中的降解机理。方法：选用12只成年雌性SD大鼠,采用改制的II型NYU装置,建立SCI组,SCI后植入HHK组,并设正常对照组,分别于术后14d取材,经HE,Mallory's－磷钨酸－苏木素,Loyer'sSterry Thionin等方法染色,观察其光镜结构的变化。结果：与损伤组相比较,植入HHK组损伤节段的萎缩程度明显,然质中部分神经元残存,有髓神经纤维脱髓鞘现象减轻,HHK周边集聚大量巨噬细胞和胶质细胞,植入的HHK毛小皮膨胀松弛,出现与皮质层分离,皮质层内出现皲裂,中央髓质腔增大,结论：植入HHK具有减轻脊髓损伤后的继发性损伤的作用,为进一步研究HHK在SCI修复过程中的作用及机理提供了形态学基础。     

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.     

不同脊髓损伤模型大鼠行为学及形态学的变化

背景：在脊髓全断模型中有切割伤模型、切除伤模型,为了更好地选择脊髓损伤修复研究的全断动物模型,有必要对这两种模型进行比较及探讨。 目的：分析不同脊髓损伤模型的行为学及病理变化,选择适用于再生研究及治疗的脊髓损伤动物模型。 方法：将160只SD大鼠随机均分为2组,分别制作切割型脊髓损伤模型与切除型脊髓损伤模型,术后1,2,4,8,10,20,30,50周内进行后肢行为学BBB评分及组织化学、免疫组织化学染色,观察损伤区残余纤维情况;术后4,10,26,52周分别在大鼠脑皮质运动区与颈髓注射BDA-FITC示踪剂,观察损伤区残余纤维的连续性。 结果与结论：切割脊髓损伤模型组大鼠术后2-50周双后肢的BBB得分明显高于切除脊髓损伤模型组(P < 0.05);切割脊髓损伤模型组在损伤区残存大量组织和神经丝、胶质纤维酸性蛋白纤维,而切除脊髓损伤模型几乎没有残存纤维;不论是切割脊髓损伤模型还是切除脊髓损伤模型,皮质脊髓束均不能通过损伤区,终止于损伤区的头端;在切割脊髓损伤模型中,脊髓固有束重新进入尾侧端的宿主脊髓组织中,而在切除脊髓损伤模型中脊髓固有束终止于损伤区的头端。表明切除脊髓损伤模型更适用于脊髓损伤后再生效果及治疗手段或药物的筛选与评价。 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      

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     

Erythropoietin-mediated preservation of the white matter in rat spinal cord injury

We investigated the effect of a single administration of recombinant human erythropoietin (rhEPO) on the preservation of the ventral white matter of rats at 4 weeks after contusive spinal cord injury (SCI), a time at which functional recovery is significantly improved in comparison to the controls [Gorio A, Necati Gokmen N, Erbayraktar S, Yilmaz O, Madaschi L, Cichetti C, Di Giulio AM, Enver Vardar E, Cerami A, Brines M (2002) Recombinant human erythropoietin counteracts secondary injury and markedly enhances neurological recovery from experimental spinal cord trauma. Proc Natl Acad Sci U S A 99:9450-9455; Gorio A, Madaschi L, Di Stefano B, Carelli S, Di Giulio AM, De Biasi S, Coleman T, Cerami A, Brines M (2005) Methylprednisolone neutralizes the beneficial effects of erythropoietin in experimental spinal cord injury. Proc Natl Acad Sci U S A 102:16379-16384]. Specifically, we examined, by morphological and cytochemical methods combined with light, confocal and electron microscopy, i) myelin preservation, ii) activation of adult oligodendrocyte progenitors (OPCs) identified for the expression of NG2 transmembrane proteoglycan, iii) changes in the amount of the chondroitin sulfate proteoglycans neurocan, versican and phosphacan and of their glycosaminoglycan component labeled with Wisteria floribunda lectin, and iv) ventral horn density of the serotonergic plexus as a marker of descending motor control axons. Injured rats received either saline or a single dose of rhEPO within 30 min after SCI. The results showed that the significant improvement of functional outcome observed in rhEPO-treated rats was associated with a better preservation of myelin in the ventral white matter. Moreover, the significant increase of both the number of NG2-positive OPCs and the labeling for Nogo-A, a marker of differentiated oligodendrocytes, suggested that rhEPO treatment could result in the generation of new myelinating oligodendrocytes. Sparing of fiber tracts in the ventral white matter was confirmed by the increased density of the serotonergic plexus around motor neurons. As for chondroitin sulfate proteoglycans, only phosphacan, increased in saline-treated rats, returned to normal levels in rhEPO group, probably reflecting a better maintenance of glial-axolemmal relationships along nerve fibers. In conclusion, this investigation expands previous studies supporting the pleiotropic neuroprotective effect of rhEPO on secondary degenerative response and its therapeutic potential for the treatment of SCI and confirms that the preservation of the ventral white matter, which contains descending motor pathways, may be critical for limiting functional deficit.