Hyperbaric oxygen intervention on expression of hypoxia inducible factor-1α and vascular endothelial growth factor after spinal cord injury models in rats

【Abstract】Objective: To observe the change of expression of Hypoxia inducible factor-1α (HIF-1α) and Vascular endothelial growth factor (VEGF) after spinal cord injury at different time and to investigate the Neuroprotective mechanism of hyperbaric oxygen (HBO) on spinal cord injury (SCI) in rats. Methods: 160 adult Sprague-Dawley rats, weighing between 250g and 300g,were randomly assigned to 4 experimental groups (n=40 per group). SCI group: SCI was created with special NYU impactor of Allen’s by a 25gram-centimeter (GCM) impacting energy on T10 of the spinal cord. SCI HBO group: hyperbaric oxygen therapy after spinal cord injury model was established. Sham operation（SH）group: only laminectomy of T10 and no impact on the spinal cord was done. SH HBO group: hyperbaric oxygen therapy after sham operation. The hindlimb functional recovery was evaluated using Basso Beattie Bresnahan (BBB) score and the expression of HIF-1α and VEGF were observed with fluorescent quantitation PCR and Western-Blot method of six rats picked randomly from each group at different times of 1, 3, 7 and 14 days after operation. Result: Rats in the SCI group and SCI HBO group were paralyzed completely after operation with BBB 0-1 score. Rats in the SH group and SH HBO group could walk after sham operation with BBB 20-21 score. The BBB scores of rats in SCI HBO group was higher than that in SCI group at 7d and 14d time point obviously (P＜0.05);The expression of HIF-1α and VEGF in SCI group and SCI HBO group was higher than in SH group and SH HBO group at any time point obviously (P＜0.05);while the SCI HBO group presented the least expression of HIF-1α at 3d,7d and 14d time points (P＜0.05) and more expression of VEGF at 7d and 14d (P＜0.05) than that of the SCI group with significant difference. Conclusion: The experimental research showed HBO could improve the hind limb functional recovery after SCI in rats;The higher expression of HIF-1α and VEGF could promote repair of damaged spinal cord after SCI;The elevation and duration of the expression of VEGF and the expression of HIF-1α by HBO intervention maybe inversely related in the repair of damaged spinal cord and neuroprotective effect.     

高压氧治疗脊髓损伤的疗效评价

目的 评价高压氧(HBO)治疗脊髓损伤患者功能恢复的疗效.方法 将130例脊髓损伤患者分为HBO组70例和对照组60例,对照组只单纯采用常规外科治疗,HBO组在常规外科治疗的基础上再配合HBO治疗.结果 HBO组功能恢复总有效率为94.3%,对照组为66.7%,HBO组临床疗效明显高于对照组,差异有统计学意义(P＜0.05).结论 HBO配合临床常规外科治疗,能促进脊髓功能恢复,明显提高疗效,降低致残率. Abstract： Objective To evaluate the effect of hyperbaric oxygen (HBO) treatment of functional recovery in patients with spinal cord injury. Methods One hundred and thirty patients with spinal cord injury were divided into HBO group (70 cases) and the control group (60 cases), the control group was treated with only routine surgical treatment,while HBO group on the basis of routine surgical treatment, together with HBO therapy. Results The total effective rate of functional recovery on HBO group was 94.3%, the control group was 66.7%, the clinical effect of HBO group was significantly higher than that of the control group(P<0.05). Conclusions HBO with the clinical routine surgical treatment of spinal cord can promote functional recovery, markedly increase efficiency, and reduce the induced disability rate.     

Human neural stem cells promote corticospinal axons regeneration and synapse reformation in injured spinal cord of rats

Background Axonal regeneration in lesioned mammalian central nervous system is abortive, and this causes permanent disabilities in individuals with spinal cord injuries. This paper studied the action of neural stem cell （NSC） in promoting corticospinal axons regeneration and synapse reformation in rats with injured spinal cord. Methods NSCs were isolated from the cortical tissue of spontaneous aborted human fetuses in accordance with the ethical request. The cells were discarded from the NSC culture to acquire NSC-conditioned medium. Sixty adult Wistar rats were randomly divided into four groups （n=15 in each）： NSC graft, NSC medium, graft control and medium control groups. Microsurgical transection of the spinal cord was performed in all the rats at the T11. The NSC graft group received stereotaxic injections of NSCs suspension into both the spinal cord stumps immediately after transection; graft control group received DMEM injection. In NSC medium group, NSC-conditioned medium was administered into the spinal cord every week; NSC culture medium was administered to the medium control group. Hindlimb motor function was assessed using the BBB Locomotor Rating Scale. Regeneration of biotin dextran amine （BDA） labeled corticospinal tract was assessed. Differentiation of NSCs and the expression of synaptophysin at the distal end of the injured spinal cord were observed under a confocal microscope. Group comparisons of behavioral data were analyzed with ANOVA. Results NSCs transplantation resulted in extensive growth of corticospinal axons and locomotor recovery in adult rats after complete spinal cord transection, the mean BBB scores reached 12.5 in NSC graft group and 2.5 in graft control group （P〈 0.05）. There was also significant difference in BBB score between the NSC medium （11.7） and medium control groups （3.7, P〈 0.05）. BDA traces regenerated fibers sprouted across the lesion site and entered the caudal part of the spinal cord. Synaptophysin expression colocalized with BDA positive axons and neurons distal to the injury site. Transplanted cells were found to migrate into the lesion, but not scatter along the route of axon grows. The cells differentiated into astrocytes or oligodendrocytes, but not into the neurons after transplantation. Furthermore, NSC medium administration did not limit the degree of axon sprouting and functional recovery of the injured rats compared to the NSC graft group. Conclusions Human embryonic neural stem cells can promote functional corticospinal axons regeneration and synapse reformation in the injured spinal cord of rats. The action is mainly through the nutritional effect of the stem cells on the spinal cord.     

家兔脊髓缺血再灌注损伤后内皮细胞功能和血小板活化状态的动态研究

目的 探讨内皮细胞功能和血小板活化状态在脊髓缺血再灌注损伤(SCI/RI)中的意义.方法 采用Zivin法建立家兔SCI/RI模型,动态观察SCI/RI前后血浆一氧化氮(NO)和血小板a颗粒膜蛋白140(GMP140)的变化.结果 NO在I/R组缺血末期显著上升(P<0.01),I/R 2h达到峰值,与sham组比较有显著意义(P<0.01);I/R6h下降但仍有显著差异(P<0.05);GMP-140在sham组无显著变化,在I/R组缺血末期显著升高(P<0.01),I/R2h后逐渐下降到正常水平.结论 血浆NO和GMP140在SCI/RI后显著升高,表明内皮细胞受刺激/损伤和血小板过度活化参与了脊髓I/R损伤与修复病理过程.

Abstract：

Objective To study the changes of vascular endothelial cell function and platelet activation in rabbit spinal cord following ischemia-reperfusion (I/R) injury and their roles in the spinal cord injury. Methods Rabbit spinal cord I/R injury models were established using Zivin method, and the changes in plasma NO and GMP140 levels were dynamically monitored after the injury. Results Plasma NO level increased significantly in the I/R group at the end of the ischemia, and reached the peak level at 2 h of reperfusion as compared to that in sham-operated group (P<0.01). Plasma NO level decreased at 6 h of reperfusion, but still significantly higher than the level in the sham-operated group (P<0.05). Plasma GMP140 underwent no significant changes in the sham-operated group, but significantly increased in the I/R group at the end of the ischemia,followed by gradual declination to the normal level at 2 h of reperfusion. Conclusion Spinal cord I/R injury causes overexpressions of NO and GMP140, suggesting the involvement of endothelial cell injury and platelet overactivation in the pathological process and repair of spinal cord I/R injury.     

促红细胞生成素通过降低TSP-1和TGF-β表达对脊髓损伤保护作用的研究

Background Erythropoietin (EPO) functions as a tissue-protective cytokine in addition to its crucial hormonal role in red cell production and neuron protection. This study was designed to determine the erythropoietin neuron protection on experimental spinal cord trauma injury (SCI) rats by exploring the level of thrombospondin-1(TSP-1) and transforming growth factor-β (TGF-β) in the development of rats’ spinal cord injury (SCI) model. Methods Sixty Sprague–Dawley (SD) rats were divided into three groups at random (the sham operation control group, SCI group and erythropoietin treatment group). Using a weight-drop contusion SCI model in SCI group and erythropoietin treatment group, then rats were sacrificed at 24 h and 7d. BBB scores were checked as locomotor function. Pathological changes were also explored by H-E staining. The expression of TSP-1 and TGF-β were determined by immunohistochemistry staining analysis and Western Blot analysis respectively. Results Slighter locomotor dysfunction and more quickly recovered as their higher BBB scores were found in erythropoietin treatment group than that in SCI group (P < 0.01). Pathological observation also showed progressive disruption of the dorsal white and few neurons regeneration in SCI rats. TSP-1 and TGF-β expression increased at 24 h and 7 d after SCI in the injured segment. We observed TSP-1 and TGF-β expression was higher in the SCI group than in erythropoietin treatment group. Samples of spinal cord from the animals demonstrated a TSP-1 optical density of 112.2 ± 6.8 and TSP-1 positive cells were 5.7 ± 1.3 respectively. After injury, TSP-1 optical density and cell number increased to 287.2 ± 14.3 and 23.2 ± 2.6/mm2 at 24 h, 232.1 ± 13.2 and 15.2 ± 2.3/mm2 at 7 d. As to EPO treatment rats, the TSP-1 optical density and cell number decreased to 213.1 ± 11.6 and 11.9 ± 1.6/mm2 at 24 h, 189.9 ± 10.5 and 9.3 ± 1.5/mm2 at 7 d while comparing to the SCI rats (P < 0.01). TGF-β immunohistochemistry staining we couldn’t found it in sham-operated group rats. In SCI rats, optical density and positive neuron number were 291.4 ± 15.2 and 28.8 ± 4.9/mm2 at 24 h, 259.1 ± 12.3 and 23.9 ± 4.1/mm2 at 7 d, and also decreased in EPO treatment rats with 222.8 ± 11.9 and 13.7 ± 2.1/mm2 at 24 h, 196.5 ± 9.7 and 8.7 ± 2.2/mm2 at 7 d (P < 0.01). Conclusion Elevating expression of TSP-1 and TGF-β can be found in the injured segment of the spinal cord at 24h and 7d after injury, erythropoietin treatment effectively prevents pathological alterations from severer spinal cord injury via reduction the expression of TSP-1 and TGF-β.     

内源性脑源性神经生长因子在骨癌痛大鼠中的作用及其脊髓机制

目的 探讨脑源性神经牛长因子(BDNF)及其下游磷酸化细胞外信号调节蛋白激酶1/2(p-ERK1/2)在骨癌痛中的作用及其脊髓机制.方法 雌性SD大鼠60只,随机分为5组(n=12),Ⅰ组为模型对照组,Ⅱ组为骨痛痛组,Ⅲ组为模型对照组+BDNF中和抗体,Ⅳ组为骨痛痛组+IgG对照抗体;Ⅴ组为骨癌痛组+BDNF中和抗体.Ⅱ、Ⅳ和Ⅴ组于大鼠左胫骨上端注入Walker256 细胞,制备骨痛痛模型;模型对照组大鼠左胫骨上端注入Hank's液.造模后第7～9天,Ⅲ、Ⅳ和Ⅴ组鞘内分别注射BDNF中和抗体、IgG对照抗体和BDNF中和抗体15μg/10μl,1次/d,连续3 d.分别于术前及术后隔日开始测定大鼠Von-Frey阈值,并测定脊髓后角的BDNF和p-ERK1/2表达水平.结果 BDNF和p-ERK1/2在脊髓后角有共表达;术后第6～18天,与Ⅰ组比较,Ⅱ、Ⅳ组Von-Fray阈值显著下降;术后第9天,脊髓BDNF和p-ERK1/2的蛋白表达显著增加(均P<0.01);Ⅲ组上述指标的差异无统计学意义(P>0.05);与Ⅱ、Ⅳ组比较,Ⅴ组Von-Frey阈值显著增高,脊髓BDNF和p-ERK1/2的蛋白表达显著减少(均P<0.01).结论 内源性BDNF可能通过其下游的p-ERK1/2信号转导途径参与了骨癌痛大鼠痛觉过敏的形成.

Abstract：

Objective To investigate the role of brain-derived neurotrophic factor(BDNF)in pain facilitation and spinal mechanisms in the rat model of bone cancer pain.Methods The bone cancer pain model was developed by inoculated Walker 256 mammary gland carcinoma cells into the tibia medullary cavity.Sixty SD female rats were divided into 5 groups(n=12 each)randomly;group Ⅰ:contrrol group (sham operation);group Ⅱ;model group;group Ⅲ:control group+anti-BDNF intrathecal(i.t.);group Ⅳ:modeI group+control IgG i.t.;group Ⅴ:model group+anti-BDNF i.t..Anti-BDNF or control IgG was injected i.t. during 7 to 9th day.Von-Frey threshold was measured one day before operation and every 2 days after operation.On the 9th day after threshold tested,rats were sacrificed after i.t. injection of either antiBDNF or control IgG,the lumbar 4-6 spinal cord was removed.The expression of the spihal BDNF and the phosphorylation of extracellular signal-regulated protein kinase1/2(p-ERK1/2)were detected by immunohistochemistry assay and Western-Blot.Co-expression pattern of BDNF and p-ERK1/2 were determined by double-labeling immunofluorescence.Results We demonstrated the coexistence of BDNF and p-ERK1/2 in the spinal cord of rats. From the 7 to 9th day after operation,von-Frey threshold in groups Ⅱ and Ⅳ was significantly lower than that in group Ⅰ and group Ⅴ(P<0.01),group Ⅴ was remarklv higher than that in group Ⅳ(P<0.01).'The spinal BDNF and p-ERK1/2 expression in group Ⅱ or Ⅳ were significantly increased compared with that in group Ⅰ or Ⅴ(P<0.01),intrathceal anti-BDNF was significantly suppressed BDNF and P-ERK1/2 expression(P<0.01).Conclusion BDNF and p-ERK1/2 was coexistence in the spinal cord of rats,and it maybe involved in the bone cancer pain.     

Preconditioning with hyperbaric oxygen and hyperoxia induces tolerance against spinal cord ischemia in rabbits

Background:The aim of this study was to determine if the ischemic tolerance could be induced in the spinal cord by pre-treatment with hyperbaric oxygen(HBO) and what components of HBO(hyperoxia,hyperbaricity,and combination of thesetwo) were critical in the induction of tolerance againstischemic injury.Methods:In experiment1,2 1rabbits were randomly as-signed to one of three groups(n=7each) :animals in the control group received no HBO before spinal cord ischemia;animals inthe HBO- 1and H…     

Changes in the expression of platelet-derived growth factor in astrocytes in diabetic rats with spinal cord injury

Background Prospective mortality studies in the United States revealed that the mortality was elevated in diabetics compared to normal individuals following chronic spinal cord injury （SCI）. Our study was conducted to investigate the levels of platelet-derived growth factor （PDGF） of astrocytes in SCI in streptozotocin （STZ）-induced diabetic rats. Methods Thirty male Sprague-Dawley （SD） rats were randomly divided into 3 groups： SCI group, diabetic SCI group, and sham operation control group. We employed STZ-induced diabetic SD rats and a weight-drop contusion SCI model. The rats were sacrificed on day 7 after the induction of SCI. Immunohistochemistry and Western blotting analysis were used to detect the PDGF expression level. Basso, Beattie and Bresnahan locomotor rating scale （BBB） was also used to evaluate the neurological recovery level of the rats. Results PDGF positive astrocyte numbers were significantly higher and PDGF staining was more intensive in astrocytes in the SCI group than in the diabetic SCI group （P〈0.05）. The diabetic SCI group showed a slower recovery of motor function with a lower BBB score 7 days after acute spinal injury. Conclusions PDGF is an important factor for the recovery of neurological function after acute spinal injury and hyperglycemia in diabetic rats could depress the expression of PDGF in injured spinal cord. This may help to explain the slower recovery and higher mortality in diabetics after SCI.     

Inactivation of the Rho-ROCK signaling pathway to promote neurologic recovery after spinal cord injuries in rats

Background After injury,axonal regeneration of the adult central nervous system （CNS） is inhibited by myelin-derived growth-suppressing proteins.These axonal growth inhibitory proteins are mediated via activation of Rho,a small GTP-binding protein.The activated form of Rho,which is bound to GTP,is the direct activator of Rho kinase （ROCK） through serial downstream effector proteins to inhibit axonal regeneration.The objective of this study was to observe the therapeutic effect of inactivation of the Rho-ROCK signaling pathway to promote neurologic recovery after spinal cord injuries in rats.Methods One hundred and twenty adult female Sprague-Dawley rats were randomly divided into three groups.Laminectomies alone were conducted in 40 rats in the sham group.Laminectomies and spinal cord transections were performed in 40 rats in the control group （treated with normal saline administered intraperitoneally）.Laminectomies and spinal cord transections were performed in 40 rats in the fasudil-treated group （treated with fasudil administered intraperitoneally）.Neurologic recovery was evaluated before surgery and 3 days,and 1,2,3,and 4 weeks after surgery using the Basso-Beattie-Bresnahan （BBB） scale of hind limb movement.At the same time,the expression of RhoA mRNA was determined with RT-PCR.Histopathologic examinations and immunofiuorescence staining of NF were performed 1 month after surgery.Results Compared with the control group,the BBB scores of the fasudil-treated group were significantly increased and the expression of RhoA mRNA was significantly decreased.In the fasudil-treated group,a large number of NF-positive regenerating fibers was observed; some fibers crossed the slit of the lesion.Conclusion Inactivation of the Rho-ROCK signaling pathway promotes CNS axonal regeneration and neurologic recovery after spinal cord injuries in rats.     

Effect of FK506 on Expression of Hepatocyte Growth Factor in Murine Spinal Cord Following Peripheral Nerve Injury

This study is to investigate the effect of FK506 on expression of hepatocyte growth factor （HGF） in rats＇ spinal cord following peripheral nerve injury and to elucidate the mechanisms for neuroprotective property of FK506. Fifty male rats were randomly divided into normal group, injury group and treatment group. Models of peripheral nerve injury were established by bilateral transection of sciatic nerve 0.5 cm distal to piriform muscle. Then the treatment group received subcutaneous injection of FK506 （1 mg/kg） at the back of neck, while the injury group was given 0.9% saline. The L4-6 spinal cords were harvested at various time points after the surgery. Western blotting and immunofluorescent staining were used to detect the level and position of HGF in spinal cord. Immunofluorescent staining showed that HGF-positive neurons were located in anterior horn, intermediate zone and posterior horn of gray matter in normal spinal cord. Western blotting revealed that there was no significant difference in the expressions of HGF between the injury group and the normal group, while the expression of HGF was significantly higher in the treatment group than in the injury group 7 and 14 days after surgery. It is suggested that peripheral nerve injury does not result in up-regulation of the expression of HGF in spinal cord, while FK506 may induce high expression of endogenous HGF after injury thereby protecting neurons and promoting axonal outgrowth.     

Transplantation of human amniotic epithelial cells improves hindlimb function in rats with spinal cord injury

Background Human amniotic epithelial cells (HAECs), which have several characteristics similar to stem cells, therefore could possibly be used in cell therapy without creating legal or ethical problems. In this study, we transplanted HEACs into the injured spinal cord of rats to investigate if the cells can improve the rats’ hindlimb motor function. Methods HAECs were obtained from a piece of fresh amnion, labeled with Hoechst33342, and transplanted into the site of complete midthoracic spinal transections in adult rats. The rats (n=21) were randomly divided into three groups: Sham-operation group (n=7), cells-graft group (n=7), and PBS group (n=7). One rat of each group was killed for histological analysis at the second week after the transplantation. The other six rats of each group were killed for histological analysis after an 8-week behavioral testing. Hindlimb motor function was assessed by using the open-field BBB scoring system. Survival rate of the graft cells was observed at second and eighth weeks after the transplantation. We also detected the myelin sheath fibers around the lesions and the size of the axotomized red nucleus. A one-way ANOVA was used to compare the means among the groups. The significance level was set at P&lt;0.05.Results The graft HAECs survived for a long time (8 weeks) and integrated into the host spinal cord without immune rejection. Compared with the control group, HAECs can promote the regeneration and sprouting of the axons, improve the hindlimb motor function of the rats (BBB score: cells-graft group 9.0±0.89 vs PBS group 3.7±1.03, P&lt;0.01), and inhibit the atrophy of axotomized red nucleus [cells-graft group (526.47±148.42) &micro;m(2 )vs PBS group (473.69±164.73) &micro;m(2), P&lt;0.01]. Conclusion Transplantation of HAECs can improve the hindlimb motor function of rats with spinal cord injury.     

不同时间窗高压氧干预对大鼠脊髓损伤后细胞凋亡及脊髓功能恢复的影响

目的:观察不同时间窗高压氧干预下的大鼠脊髓损伤(SCI)后细胞凋亡和脊髓功能的恢复情况,探讨最佳的高压氧治疗方法(HBOT),为临床治疗SCI提供实验依据。方法:160只SD大鼠随机分为模型对照组、HBO-PC组、HBOT组和HBO-PC+HBOT组。采用Allen's打击法建立SCI模型。模型对照组大鼠仅制模,未进行任何干预;HBO-PC组大鼠于高压氧干预10 d后立即制模,制模后未进行任何干预;HBOT组大鼠于制模后立即行高压氧干预;HBO-PC+HOBT组大鼠于高压氧干预10 d后立即制模,制模后继续高压氧干预。各组大鼠分别于制模后第1、2、7和14天取材,免疫组织化学PV-9000二步法检测大鼠Fas和FasL的表达水平,光镜下观察,并对结果进行统计学分析;采用TUNEL法检测细胞凋亡指数(AI),神经功能评价采用BBB评分。结果:与模型对照组比较,HBO-PC组、HBOT组和HBO-PC+HBOT组大鼠各时间点Fas和FasL表达水平均降低,且差异均有统计学意义(P<0.01);HBO-PC+HBOT组大鼠各时间点Fas和FasL表达水平比HBOT组和HBO-PC组降低,且差异有统计学意义(P<0.05);HBOT组大鼠各时间点Fas和FasL表达水平与HBO-PC组比较差异无统计学意义(P>0.05)。与模型对照组比较,其他各组大鼠细胞AI明显降低,差异均有统计学意义(P<0.01);HBO-PC+HBOT组AI低于HBOT组和HBO-PC组,且差异有统计学意义(P<0.05);HBOT组AI与HBO-PC组比较差异无统计学意义(P>0.05)。术后7和14 d HBO-PC组、HBOT组和HBO-PC+HBOT组大鼠BBB评分均高于模型对照组,且差异有统计学意义(P<0.01);HBO-PC+HBOT组BBB评分高于HBOT组和HBO-PC组,且差异有统计学意义(P<0.05或P<0.01);HBOT组BBB评分高于HBO-PC组,且差异有统计学意义(P<0.05)。结论:高压氧干预可减少SCI后细胞凋亡,促进脊髓功能的恢复;其治疗时间窗应提前到损伤前,HBO-PC联合HBOT法是治疗SCI的较佳方案。     

大鼠脊髓针刺损伤程度与脊髓功能变化的相关性研究

目的通过观察大鼠脊髓穿刺致不同损伤程度后病理生理、运动及电生理改变,寻找对脊髓损伤程度最小的方法,为进一步研究局麻药脊髓毒性提供新的途径。方法健康SD大鼠144只随机分为对照组和实验组,实验组又分为A组(29G)、B组(25G)和C组(21G)。实验动物暴露L4-5节段间硬脊膜,直视下分别用21G、25G、29G刺伤L4-5节段脊髓,缝合切口。各组分别在术前进行双后肢运动功能评分,术后各时点记录运动功能评分(BBB评分)、电生理检测及脊髓病理观察。结果对照组麻醉恢复后能站立行走,脊髓结构正常。实验组29G组行为学评分最高,脊髓损伤区域无明显病理改变;21G组运动、脊髓电生理和组织病理的改变明显,2周时明显恢复。结论应用29G穿刺针对脊髓进行针刺对大鼠脊髓功能影响小,具有穿刺损伤小、重复性好的优点,可为研究局麻药脊髓毒性提供新途径。     

大鼠脊髓T11段全横断损伤模型的建立及护理

目的 制备大鼠脊髓T11全横断动物模型，模拟脊髓损伤，为后期的干细胞移植治疗研究提供实验依据。方法 16只健康Wistar大鼠随机分为两组：对照组（n=8）及脊髓损伤组（SCI组，n=8）。SCI组咬除T9-T10棘突及相应椎板，横切断暴露的脊髓T11，夹除约0.3-0.5cm脊髓，对照组仅行椎板切除术。术后1，3，7，14，21d分别进行BBB运动功能评分。对模型进行人工排尿、排便、悬吊鼠尾等护理措施。结果 SCI组所有动物在术后均表现出典型的脊髓截瘫症状，BBB运动功能评分很低，与对照组相比具有非常显著性差异（P〈0.01）。护理措施降低了截瘫大鼠并发症的发生。结论 建立了大鼠脊髓T11段全横断损伤模型，并摸索出了一套有效的截瘫模型的护理方法。     

羊膜间充质干细胞静脉移植治疗脊髓损伤的实验

目的:探讨羊膜间充质干细胞静脉移植对脊髓损伤修复的影响。方法:90只成年SD大鼠按改良Allen′s打击方法建立脊髓损伤模型,随机分为3组:对照组、假移植组和移植组,每组30只。于脊髓损伤后1周经尾静脉移植Brdu标记的羊膜间充质干细胞。3组大鼠分别于损伤后第1 d、3 d、1周及移植后1 d、3 d、1周、2周、4周采用BBB评分法对行为学进行评价。并于移植后1 d、3 d、1周、2周、4周分批处死,切片观察Brdu标记的细胞能否迁移到损伤区。结果:脊髓损伤后第1 d,3组实验动物后肢运动功能BBB评分皆为0分;细胞移植1周后移植组动物BBB评分为5.6±0.6,对照组和假移植组动物BBB评分分别为5.3±0.4和5.2±0.6;细胞移植2周后移植组、假移植组和对照组BBB评分分别为11.3±0.9、6.4±0.5和6.5±0.8;4周后3组实验动物评分分别为13.4±0.9、8.3±0.6和8.5±0.7;在损伤部位出现了Brdu标记的羊膜间充质干细胞。结论:经静脉移植的羊膜间充质干细胞能够迁移到损伤区并对脊髓损伤有一定的修复作用。     

淫羊藿苷可减轻大鼠脊髓损伤后的脂质过氧化

目的研究淫羊藿苷对大鼠脊髓损伤后脂质过氧化的影响。方法72只健康成年清洁级雄性SD大鼠按随机数字表法分为 淫羊藿苷组、对照组及假手术组3组,每组24只。对照组和淫羊藿苷组采用改良Allen法制作脊髓损伤模型,假手术组仅切开椎 板不损伤脊髓。术后即刻淫羊藿苷组给予淫羊藿苷（100 mg/kg）灌胃,对照组和假手术组给予等量生理盐水灌胃,1次/d。术后 24 h采用硫代巴比妥酸法检测丙二醛（MDA）含量,黄嘌呤氧化酶法检测超氧化物歧化酶（SOD）活性;采用干湿重法检测脊髓 组织的含水量;术后48 h 采用透射电镜观察脊髓组织超微结构,并采用Kaptanoglu 评分法进行超微结构评分;术后7、14、21、 28 d采用BBB评分法评定大鼠运动功能。结果术后24 h对照组和淫羊藿苷组MDA含量显著高于假手术组,淫羊藿苷组低于 对照组,差异有统计学意义（P<0.05）;对照组和淫羊藿苷组SOD活性显著低于假手术组,淫羊藿苷组高于对照组,差异有统计学 意义（P<0.05）。术后48 h,对照组和淫羊藿苷组脊髓组织含水量、超微结构评分均显著高于假手术组,淫羊藿苷组均显著低于 对照组（P<0.05）。术后各时间点对照组和淫羊藿苷组大鼠BBB评分均低于假手术组,差异有统计学意义（P<0.05）;淫羊藿苷组 大鼠BBB评分高于对照组,差异有统计学意义（P<0.05）。结论淫羊藿苷能够明显降低脊髓损伤后的MDA含量,升高SOD的 活性,减轻脂质过氧化、脊髓水肿和脊髓的组织病理学损伤,改善脊髓损伤大鼠的运动功能,有效地保护脊髓组织和神经作用。     

预防使用米诺环素对胸段脊髓全横断大鼠运动功能恢复的影响

目的：观察预防使用米诺环素对脊髓全横断大鼠运动功能的作用。方法：30只雄性Wistar大鼠随机分为3组,假手术组、脊髓横断模型组和米诺环素预处理组,每组10只大鼠。米诺环素预处理组大鼠术前腹腔注射米诺环素（90mg/kg）。各组大鼠于术后1、7、14、21d应用改良Tarlov评分和BBB评分方法对大鼠后肢行为功能进行评价。第22d将所有实验大鼠处死后取损伤段脊髓,行HE染色。结果：术后第1d,脊髓横断模型组和米诺环素预处理组大鼠Tarlov评分障碍率、BBS评分比较无明显差别（P〉0.05）;米诺环素预处理组术后第7d到第21dTarlov评分障碍率明显低于脊髓横断模型组,BBB评分明显高于脊髓横断模型组（P〈0.01）。HE染色结果显示,脊髓横断模型组大鼠脊髓出现明显病理变化,米诺环素预处理组大鼠脊髓的病理变化明显减轻。结论：预防使用米诺环素可明显促进胸段脊髓横断大鼠运动功能的恢复。     

重复高压氧预处理对大鼠脊髓缺血再灌注损伤时糖调节蛋白78表达的影响

目的探讨重复高压氧预处理对大鼠脊髓缺血再灌注损伤保护中糖调节蛋白78(GRP78)表达的影响。方法雄性SD大鼠36只,体重250～300g,采用随机数字表法,将其随机分为3组(n=12)假手术组(S组)、脊髓缺血再灌注组(I/R组)和重复高压氧预处理(HOP组)。HOP组采用高压氧预处理[1000ml/L O2,2.5 atmosphere absolute(ATA),1h/d,5天],最后一次处理后24h,I/R组和HOP组采用Zivin法制备脊髓缺血再灌注模型(缺血15min,再灌注1h),24、48、72h后分别评价后肢运动功能,然后处死大鼠,取L5～7节段脊髓组织,测定GRP78的mRNA及其蛋白表达水平,光镜下观察病理学结果。结果与S组比较,I/R组和HOP组后肢运动功能和脊髓前角正常运动神经元计数降低,脊髓组织GRP78 mRNA及蛋白表达水平上调(P<0.05);与I/R组比较,HOP组后肢运动功能和脊髓前角正常运动神经元计数升高,脊髓组织GRP78 mRNA及蛋白表达水平上调(P<0.05)。HOP组脊髓组织病理学损伤程度轻于I/R组。结论重复高压氧预处理可上调大鼠脊髓缺血再灌注时GRP78表达,从而减轻大鼠脊髓缺血再灌注损伤。     

嗅鞘细胞移植促进急性脊髓损伤的修复作用

目的研究嗅鞘细胞(OEG)移植后在体内存活情况以及对大鼠脊髓损伤长期的修复作用.方法用新生Wistar大鼠嗅球做OEG培养,大量增殖并标记.80只大鼠,随机分为4组,每组20只.A、B、C组以250 mm·g打击T13脊髓致运动诱发电位和体感诱发电位完全消失,A组在打击区中央用尖刀横行切断脊髓;D组仅做与A、B组相同节段的椎板减压,不挫伤脊髓.A、B组在脊髓远近断端距离挫伤区边缘1 mm的脊髓中线上,深度分别为1.75、1.5、1.0、0.5 mm处,各注入200 000个OEG;C组用同样的方法注射等量的DMEM培养液;D组不做处理.术后观察脊髓功能恢复情况(BBB运动功能评分法)和体重变化.术后24周取脊髓标本,做HE染色、嗜银染色、抗神经原纤维(NF)免疫组化染色、荧光显微镜下观察Hoechst标记的OEG在体内存活情况.结果手术后4周,A、B、C组开始有运动功能恢复,术后4～24周BBB运动功能评分A、B组均高于C组(P＜0.01),16周以后BBB评分变化较小.HE染色A、B两组脊髓损伤区结构紊乱,纤维走行方向扭曲不一致,细胞数目较多,C组大鼠脊髓损伤段常有明显空洞存在,纤维含量少且扭曲.嗜银染色和免疫组化抗NF染色显示无论在损伤区还是损伤头、尾端,A、B组神经纤维数量多于C组,但都少于相同节段的D组(P＜0.01).荧光显微镜下观察到Hoechst标记的OEG大量存在于脊髓损伤段周围.术后各组大鼠均出现体重减轻.术后2周,D组大鼠体重恢复至术前重量,此后逐渐增加.术后4周,A、B、C组大鼠体重降至最低,与D组(Sham组)比较差异有显著性(P＜0.01);此后,A、B组大鼠体重逐渐增加,而C组大鼠体重增加不明显;A、B组大鼠体重与C组比较差异有显著性(P＜0.05).结论OEG移植具有一定促进脊髓损伤神经纤维再生和功能恢复的作用.     

神经干细胞在体外诱导向胆碱能神经元定向分化后移植治疗脊髓损伤

目的 研究神经干细胞向胆碱能神经元定向分化后对脊髓横断损伤的修复作用.方法 采用GFP转基因孕鼠(E 12～14d)的海马分离、培养神经干细胞并诱导其向胆碱能神经元方向分化.SD成年大鼠以显微剪横断脊髓制成SCI模型.将SD大鼠18只分为3组:A组注入DMEM/F12培养液;B组注入神经于细胞的细胞液,C组注入在体外定向诱导为胆碱能神经元的细胞液;3组实验动物均于细胞移植后采用B B B评分法定期评估运动功能.于移植后第8周末,取出相应的脊髓阶段,行ChAT免疫组织化学染色,光镜观察.结果 从海马分离的细胞群具有自我更新能力,表达nestin,胎鼠骨骼肌提取液可以诱导这些细胞中的11.8%分化成为胆碱能神经元,与对照组差异明显.B组和C组所有大鼠BBB评分在移植细胞3周以后明显高于A组(P＜0.05),C组所有大鼠BBB评分在移植细胞4周以后明显高于B组(P＜0.05).在移植第8周末,冰冻切片中可见ChAT染色阳性细胞.结论 神经干细胞可以在体外诱导向胆碱能神经元定向分化,定向分化后移植应用在脊髓横断损伤治疗中,可明显改善运动功能.