神经干细胞移植联合腹腔注射促红细胞生成素对横断性脊髓损伤大鼠神经轴突的修复作用

目的: 探讨神经干细胞(NSCs)与促红细胞生成素(EPO)共同作用于横断性脊髓损伤大鼠后对损伤区轴突的修复作用,为临床治疗脊髓损伤提供理论依据。方法: 40只雌性成年Wistar大鼠,建立T10全横断大鼠脊髓损伤模型后,随机分为对照组、NSCs组、EPO组和联合治疗组,每组10只。术后8周采用BDA皮质脊髓束顺行追踪法和荧光金(FG)皮质脊髓束逆行追踪法评估损伤区脊髓神经轴突再生情况,同时分期采用实验性脊髓损伤运动功能BBB评分法评价大鼠后肢功能恢复情况。结果: BDA 免疫荧光染色和FG免疫荧光染色,联合治疗组可见大量被BDA-cy3红色荧光标记的再生轴突,其中部分再生轴突穿越损伤区到达远端;NSCs组仅见少量轴突再生,无神经轴突通过脊髓损伤区;EPO组偶见散在的神经纤维再生;对照组无明显的轴突再生。联合治疗组大脑皮质中可见少量被FG标记的椎体细胞及轴突发出金黄色荧光,其余3组大脑皮质中无FG标记细胞。大鼠后肢功能BBB评分,在术后1周及1周以后各时段,联合治疗组大鼠BBB评分均高于其他各组(P<0.05)。结论: 脊髓损伤后移植NSCs联合腹腔注射EPO可有效促进脊髓损伤区神经轴突的再生以及脊髓损伤大鼠后肢运动功能的恢复。     

神经干细胞移植联合促红细胞生成素对大鼠脊髓损伤的修复作用

目的:观察神经干细胞(NSCs)联合促红细胞生成素(EPO)对横断性大鼠脊髓损伤的修复作用,为临床治疗脊髓损伤提供理论依据。方法:40只成年雌性Wistar大鼠建立大鼠T10全横断脊髓损伤模型,并随机分为对照组、NSCs组、EPO组和NSCs+EPO组,每组10只。术后8周采用NF-200免疫组织化学染色和免疫荧光染色对各组大鼠损伤区脊髓神经纤维再生情况进行形态学观察;应用BBB评分评估各组大鼠后肢运动功能恢复情况。结果:组织形态学观察,对照组大鼠横断处脊髓组织残端萎缩,脊髓白质和灰质间可见大量空洞形成,未见有明显的神经纤维再生;NSCs+EPO组大鼠横断处脊髓组织残端轻度萎缩,横断区可见大量呈杂乱、无序生长的神经纤维,可见有连续性神经纤维通过脊髓横断区,脊髓白质和灰质间可见少量空洞形成。NSCs+EPO组大鼠中,FITC共轭抗神经丝蛋白抗体NF-200标记的再生神经纤维在横断区头侧大量再生,呈无序状生长,并通过损伤区到达尾侧;NSCs组大鼠可见少量神经纤维再生,未通过损伤区到达尾侧。NSCs+EPO组大鼠后肢运动功能BBB评分,术后7 d内均高于其他各组(P<0.05);NSCs组大鼠后肢运动功能BBB评分术后7 d内均高于对照组和EPO组(P<0.05)。结论:NSCs移植联合腹腔注射EPO可有效促进大鼠损伤脊髓功能的恢复、轴突的存活和再生。     

Functional recovery following traumatic spinal cord injury mediated by a unique polymer scaffold seeded with neural stem cells and Schwann cells

Background The most important objective of transplant studies in the injured spinal cord has been to provide a favorable environment for axonal growth. Moreover, the continuing discovery of new grafts is providing new potentially interesting transplant candidates. Our purpose was to observe the morphological and functional repair effects of the co-transplantation of neural stem cell （NSC）, Schwann ceils （SCs） and poly lactide-co-glycolide acid （PLGA） on the spinal cord injury of rats.Methods A scaffold of PLGA was fabricated. NSCs and SCs were cultured, with the NSCs labeled with 5-bromodeoxyuridine, and the complex of NSC/PLGA or NSC＋SCs/PLGA were constructed. Thirty-six Wistar rats were randomly divided into three groups： group A （transplantation of PLGA）, group B （transplantation of NSC/PLGA） and group C （transplantation of NSC＋SCs/PLGA）. The 3 mm length of the right hemicord was removed under the microscope in all rats. The PLGA or the complex of PLGA-celIs were implanted into the injury site. Basso-Beattie-Bresnahan （BBB）locomotion scores, motor and somatosensory evoked potential of lower limbs were examined to learn the rehabilitation of sensory and motor function at 4 weeks, 8 weeks, 12 weeks and 24 weeks after injury. All the recovered spinal cord injury （SCI） tissues were observed with HE staining, immunohistochemistry, and transelectronmicroscopy to identify the survival, migration and differentiation of the transplanted cells and the regeneration of neural fibres at 4 weeks, 8 weeks,12 weeks and 24 weeks after injury.Results （1） From 4 weeks to 24 weeks after injury, the BBB locomotion scores of cell-transplanted groups were better than those of the non-cell-transplanted group, especially group C （P 〈0.05）. The amplitudes of the somatosensory evoked potential （SEP） and motor-evoked potential （MEP） were improved after injury in groups B and C, but the amplitude of SEP and MEP at 4 weeks was lower than that at 12 weeks and 24 weeks after injury. Compared with group B, the amplitude of SEP and MEP in group C was improved. The amplitude of SEP and MEP was not improved after injury in group A. （2） HE staining revealed the volume of the scaffold decreased and the number of cells in the scaffold increased. Newly-grown capillaries also could be seen. Immunohistochemistry staining showed the transplanted NSCs could survive and migrate until 24 weeks and they could differentiate into neurons and oligodendrocytes. The regenerated axons were observed in the scaffold-cell complex with transelectronmicroscopy. The above manifestations were more extensive in group C.Conclusions The transplanted NSC can survive and migrate in the spinal cord of rats up to 24 weeks after injury, and they can differentiate into various neural cells. Co-transplantation of cells/PLGA can promote the functional recovery of the injured spinal cord. The effect of co-transplanting NSC＋SCs/PLGA is better than transplanting NSC/PLGA alone.     

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.     

TGF-β1和CNTF在大鼠移植神经干细胞后的损伤脊髓中的表达

目的 研究在受损伤脊髓移植神经干细胞后对其TGF-β1和CNTF表达的影响.方法 将正常成年SD雌性大鼠35只,分为:单纯脊髓全横断组、假手术组、NSCs移植组.NSCs移植组在脊髓全横断后第7天时进行NSCs移植,其它2组不移植NSCs;通过RT-PCR测定脊髓损伤局部头侧在移植术后3,7,14 d TGF-β1和CNTF的表达.结果 移植术后3 d,7 d,单纯全横断组TGF-β的表达大于神经干细胞组.CNTF仅在术后7 d,前者表达大于后者,其余时间段2组间2因子的表达无统计学意义.结论 神经干细胞移植使脊髓损伤局部TGF-β1的表达降低,但对CNTF表达的影响不大.     

神经干细胞与骨髓间充质干细胞移植对脊髓损伤修复的比较

目的:比较神经干细胞和骨髓间充质干细胞移植治疗脊髓损伤效果与机制的差异。方法:用成年Wist-ar大鼠建立脊髓半横切模型,随机分为神经干细胞(NSCs)组(n=10)、骨髓间充质干细胞(BMSC)注射组(n=10)、PBS注射组(n=10)及只打开椎板的假手术组(n=10)。移植后行BBB运动功能学评分,半切位置的免疫组化及核磁成像比较。结果:BBB评分NSCs注射组明显高于BMSCs注射组,NSCs注射组和BMSCs注射组均明显高于PBS注射组,脊髓切片中可观察到被标记的NSCs及BMSCs,核磁成像显示移植后半切形成的脊髓空洞有所减小。结论:静脉注射NSCs、BMSCs均能改善脊髓损伤大鼠的运动功能,但注射NSCs效果更明显。静脉注射干细胞后,细胞可迁移至脊髓损伤的位置,核磁成像显示脊髓空洞有所减小,提示干细胞可能通过补充或替代损失的神经细胞,修复已缺失的神经组织和功能性神经单位,重建神经环路。     

Co-transplantation of neural stem cells and Schwann cells within poly (L-lactic-co-glycolic acid) scaffolds facilitates axonal regeneration in hemisected rat spinal cord

Background  Various tissue engineering strategies have been developed to facilitate axonal regeneration after spinal cord injury. This study aimed to investigate whether neural stem cells (NSCs) could survive in poly(L-lactic-co-glycolic acid) (PLGA) scaffolds and, when cografted with Schwann cells (SCs), could be induced to differentiate towards neurons which form synaptic connection and eventually facilitate axonal regeneration and myelination and motor function.

Methods  NSCs and SCs which were seeded within the directional PLGA scaffolds were implanted in hemisected adult rat spinal cord. Control rats were similarly injured and implanted of scaffolds with or without NSCs. Survival, migration, differentiation, synaptic formation of NSCs, axonal regeneration and myelination and motor function were analyzed. Student’s t test was used to determine differences in surviving percentage of NSCs. One-way analysis of variance (ANOVA) was used to determine the differences in the number of axons myelinated in the scaffolds, the mean latency and amplitude of cortical motor evoked potentials (CMEPs) and Basso, Beattie & Bresnahan locomotor rating scale (BBB) score. The χ² test was used to determine the differences in recovery percentage of CMEPs.

Results  NSCs survived, but the majority migrated into adjacent host cord and died mostly. Survival rate of NSCs with SCs was higher than that of NSCs without SCs ((1.7831±0.0402)% vs. (1.4911±0.0313)%, P <0.001). Cografted with SCs, NSCs were induced to differentiate towards neurons and might form synaptic connection. The mean number of myelinated axons in PLGA+NSCs+SCs group was more than that in PLGA+NSCs group and in PLGA group ((110.25±30.46) vs. (18.25±3.30) and (11.25±5.54), P <0.01). The percentage of CMEPs recovery in PLGA+NSCs+SCs group was higher than in the other groups (84.8% vs. 50.0% and 37.5%, P <0.05). The amplitude of CMEPs in PLGA+NSCs+SCs group was higher than in the other groups ((1452.63±331.70) µV vs. (428.84±193.01) µV and (117.33±14.40) µV, P <0.05). Ipsilateral retransection resulted in disappearance again and functional loss of CMEPs for a few days. But contralateral retransection completely damaged the bilateral motor function.

Conclusions  NSCs can survive in PLGA scaffolds, and SCs promote NSCs to survive and differentiate towards neurons in vivo which even might form synaptic connection. The scaffolds seeded with cells facilitate axonal regeneration and myelination and motor function recovery. But regenerating axons have limited contribution to motor function recovery.

 

     

NT-3-HUMSCs联合基因沉默SOCS3治疗SD大鼠脊髓损伤后的神经再生修复

目的 NT-3-HUMSCs联合基因沉默SOCS3治疗SD大鼠脊髓损伤, 以期促进损伤神经再生修复.方法 (1) 用贴壁法体外培养人脐带间充质细胞 (HUMSC) , 同时进行分离, 提纯和鉴定; (2) 构建NT-3基因真核表达载体, 利用基因转染技术将其转入HUMSC, 构建NT-3-HUMSC细胞, 体外检测其存活情况及NT-3表达情况; (3) 筛选作用于SOCS3的特异性靶点, 进行序列同源性分析, 设立阴性对照, 设计并合成SOCS3-siRNA, 同时在体外检测功能; (4) 建立SD大鼠脊髓损伤模型分为为:I.假手术组10只;Ⅱ.T12全脊髓横断损伤模型40只, 随机分为4组, 生理盐水治疗组10只;siRNA+NT-3-HUMSCs治疗组10只;NT-3-HUMSCs治疗组10只;SOCS3-siRNA治疗组10只.以上各组造模成功后, 分别存活12周进行神经电生理监测; (5) 对SD大鼠进行灌注固定和取材, 观察局部胶质疤痕降解情况和轴突再生情况, 同时运用生物素化葡聚糖 (BDA) 荧光顺行追踪取损伤移植区-宿主交界处头尾侧脊髓组织, 镜下观察皮质脊髓束再生的情况.结果 (1) siRNA+NT-3-HUMSCs治疗组较生理盐水治疗组横断脊髓空洞明显缩小, 差异有统计学意义 (P<0.05) ; (2) BDA顺行追踪结果表明siRNA+NT-3-HUMSCs治疗组较生理盐水治疗组神经轴突生长明显; (3) 神经电生理检测损伤12周后治疗组P40潜伏期较假手术组缩短, siRNA+NT-3-HUMSCs治疗组较生理盐水治疗组比较潜伏期缩短明显, 波幅升高明显, 差异有统计学意义 (P<0.05) .结论 NT-3-HUMSCs联合基因沉默SOCS3治疗SD大鼠脊髓损伤, 可以促进损伤神经再生修复.     

bcl-2基因修饰神经干细胞移植修复大鼠脊髓损伤

目的探讨bcl-2基因修饰神经干细胞移植对脊髓损伤大鼠损伤神经功能恢复的影响。方法体外培养大鼠神经干细胞,经Ad-EGFP为载体介导端B淋巴细胞瘤-2基因(bcl-2)基因转染神经干细胞,分为3组:对照组、阴性转染组、bcl-2转染组。Western-blot检测神经干细胞在转染前后bcl-2蛋白的表达。成年雌性SD大鼠85只,造模成功72只,随机分为对照组,NSCs组,bcl-2-NSCs组,24只/组,按照改良的Allen打击法建立大鼠急性脊髓损伤模型。通过BBB评分、斜板试验进行运动功能评定。造模后7 d通过RT-PCR及Western-blot检测检测脊髓损伤区周围HSP27、c-fos基因的表达,TUNEL法检测细胞凋亡情况。造模后4周取材行病理切片HE染色及荧光显微镜观测EGFP标记的NSC存活及分布情况,通过SEP和MEP观察大鼠神经电生理恢复情况。结果 bcl-2基因转染大鼠神经干细胞后,bcl-2转染组与对照组、阴性转染组相比bcl-2基因和蛋白水平均有表达(P0.05);大鼠下肢运动功能评价bcl-2-NSCs组优于NSCs组,NSCs组优于对照组。造模后72 h,bcl-2-NSCs组细胞凋亡数均明显低于对照组和NSCs组(P0.05)。造模后7 d,与对照组和NSCs组相比,bcl-2-NSCs组HSP27基因和蛋白的表达均较显著升高(P0.05),bcl-2-NSCs组c-fos基因和蛋白的表达较显著降低(P0.05)。造模后4周,HE染色对照组可见脊髓组织缺失及脊髓空洞形成,无神经轴索通过。NSCs组损伤区可见少量神经轴索样结构,脊髓空洞较小,bcl-2-NSCs组可见较多神经轴索样结构,未见脊髓空洞。EGFP标记的阳性细胞数:bcl-2-NSCs组最多,NSCs组次之,对照组未见,且各组之间差异有显著性(P0.05)。造模后4周,SEP和MEP的潜伏期:bcl-2-NSCs组NSCs组对照组,且各组之间差异有显著性(P0.05);波幅:bcl-2-NSCs组NSCs组对照组,且各组之间差异有显著性意义(P0.05)。结论通过Ad-EGFP为载体介导端B淋巴细胞瘤-2基因(bcl-2)基因转染使神经干细胞能够促进体外培养的大鼠神经干细胞增殖。bcl-2基因修饰神经干细胞移植可促进脊髓损伤大鼠神经突触的再生,升高脊髓损伤区HSP27表达,降低脊髓损伤区bcl-2基因的表达和神经细胞凋亡,改善大鼠的肢体运动功能和电生理功能。     

神经干细胞移植治疗大鼠脊髓损伤

目的：探讨神经干细胞移植治疗脊髓损伤的新方法，为治疗脊髓功能障碍性疾病打下基础，方法：制作脊髓横断大鼠模型，造成大鼠下肢瘫痪，分别在损伤急性期和损伤3周后移植胎鼠组织神经干细胞，观察移植后的动物行为变化，脊髓神经电生理变化和脊髓组织形态学变化，结果：细胞移植后第8d即可见瘫痪大鼠的后肢肌力开始恢复，2－3周后可出现爬行，4周后后肢活动沃跃；对照组瘫痪的肢体无任何恢复。脊髓诱发电位部分出现，动作电位波幅较高，对照组未出现诱发电位，且动作电位波幅明显减低，脊髓移植肉眼可见有增生的组织充填，镜下有大量新生的细胞，表现为神经元和神经胶质细胞阳性染色，结论：神经干细胞移植可使脊髓横断大鼠运动功能恢复，有望成为治疗脊髓损的有效手段。     

GDNF基因体内转染对大鼠脊髓损伤后轴突再生的影响

目的：研究脂质体介导的胶质细胞源性神经营养因子（GDNF）基因在大 鼠损伤脊髓内的表达,观察外源性GDNF对损伤脊髓轴突再生的作用。方法：利用Nystrom法制备大鼠胸髓压迫损伤模型。以直接注射法将脂质体DC－Chol和重组质粒pEGFP－GDNF cDNA混合后注入大鼠损伤脊髓。采用RT－PCR技术和荧光显微镜检测GDNF基因转染后的体内表达,并通过辣根过氧化酶（HRP）顺行追踪技术和神经微丝（NF）、胶质原纤维酸性蛋白（GFAP）免疫组化活性的变化来评价GDNF基因转染对轴突再生的影响。结果：经脂质体DC－Chol介导GDNF基因可有效地转染脊髓组织 中并得到表达。GDNF转基因4周后可明显增加NF阳性轴突数目,促进皮质脊髓束再生并通过损伤区。结论：外源性GDNF在损伤区局部高表达具有神经损伤保护作用,提示阳离子脂质体介导GDNF体内转基因治疗创伤性脊髓损伤的方法是可行的。     

大鼠脊髓损伤BDNF基因修饰神经干细胞移植后HRP逆行示踪

目的：检测大鼠脊髓损伤脑源性神经营养因子（Brain-derived neurotrophic factor,BDNF)基因修饰神经干细胞移植后，神经纤维的再通及后肢功能恢复情况。方法：大鼠L4脊髓全横断后，在横断处立即移植BDNF基因修饰神经干细胞，分四个时相点（1周，1、2、3个月）进行辣根过氧化物酶（HRP）逆行示踪，并观察损伤移植处的形态学变化及大鼠后肢运动功能恢复情况。结果：损伤移植处脊髓的形态学明显好转；损伤移植处上段脊髓中，移植1个月组有HRP阳性细胞，以后两组逐渐增多；移植组大鼠后肢运动功能明显恢复。结论：大鼠脊髓损伤BDNF基因修饰神经干细胞移植后，在损伤移植处有HRP阳性神经元和神经纤维，大鼠后肢运动功能明显恢复，提示BDNF基因修饰神经干细胞有修复大鼠脊髓损伤的作用。     

神经干细胞移植治疗损伤脊髓的实验研究

目的 探讨异体胚胎神经干细胞(neural stem cell，NSC：)移植修复治疗损伤脊髓的疗效。方法 由胚胎SD鼠大脑海马区脑组织培养出NSC，经传代、5-溴脱氧尿嘧啶(BrdU)标记后植入按Allen法制成的SD鼠的损伤脊髓内，术后观察鼠的行为改变、斜板试验及改良运动功能Tarlov评分评价功能恢复；体感诱发电位(SEP)和磁刺激运动诱发电位(MEP)监测脊髓感觉及运动电位传递；光镜及电镜观察植入区组织结构；以示踪剂麦胚凝集素。辣根过氧化物酶(WGA-HRP)显色观察轴突的生长及功能恢复；以免疫组化方法检测神经胶质原纤维酸性蛋白(GFAP)和饱和硫蛋白(S100)阳性细胞。结果 NSC在损伤脊髓中能成活并分化为神经元及神经胶质细胞，有轴突形成，分化倾向于神经元，能迁移1cm距离。WGA—HRF，能被运输到挫伤以外区域，运动电位能传递到损伤区远端，行为学观察受试组优于对照组。结果 异体胚胎NSC能在损伤区替代受损的神经元及神经胶质细胞，形成神经轴突联系，使损伤的脊髓功能得到一定程度的恢复。     

大鼠脊髓损伤亚急性期NSCs脊髓内移植对脊髓神经电生理的影响

目的 研究神经脊髓损伤的亚急性期(第7天)神经干细胞(neural stem cells,NSCs)脊髓内移植对大鼠受损伤脊髓神经电生理的影响.方法 正常成年SD雌性大鼠15只,分为3组:单纯全横断组、假手术组和神经干细胞移植组.测定3组大鼠的皮层体感诱发电位(cortical somatosensory evoked potential,CSEP)、运动诱发电位(motion evoked potential,MEP)和电针刺激大脑皮质运动区.结果 神经干细胞移植组的诱发电位CSEP、MEP的潜伏期短于单纯脊髓全横断组大鼠,电针刺激大脑皮质运动区发现NSC移植组大鼠双后肢出现明显收缩,且以对侧更为明显.结论 神经干细胞脊髓内移植后能部分促进损伤脊髓的感觉和运动传导功能的恢复.     

神经干细胞移植治疗大鼠脊髓损伤的活体示踪研究

目的:探索利用MR技术活体追踪干细胞的可行性及神经干细胞(NSCs)移植对大鼠脊髓损伤(SCI)后功能恢复的影响。方法:66只SD大鼠随机分为假损伤组(A组)、SCI对照组(B组)和细胞移植治疗组(C组)3组,应用已包被多聚左旋赖氨酸(PLL)的SPIO标记NSCs,对标记细胞进行普鲁士蓝染色,分别在细胞移植后第1、2、3、4、5周对各组动物进行BBB评分,细胞移植后1、3、5周行MRI检查。结果:(1)普鲁士蓝染色证实该方法标记NSCs的有效率为100%。(2)细胞移植后1~5周,B、C组动物运动功能均有不同程度恢复,但B组恢复较慢,BBB评分差异有统计学意义(P<0.05)。(3)1.5 T MRI检查见移植处在T2WI序列呈低信号改变,第3周时低信号向损伤区扩大,第5周时可在损伤区见到低信号改变。结论:MR技术可以活体追踪干细胞,NSCs移植治疗SCI有利于大鼠后肢功能的恢复。     

三七总皂甙对大鼠脊髓损伤后神经功能恢复作用的研究

目的探讨三七总皂甙对大鼠脊髓半横断损伤后组织结构及运动功能恢复的作用。方法参考Ram—berg和Borgens法建立大鼠半横断型脊髓损伤模型，45只Sprague—Dawley大鼠均接受T10节段的脊髓损伤，然后被随机分为三七总皂甙、甲基强的松龙和空白对照组，所有大鼠分别在脊髓损伤后第1、3、7、14和21天接受斜板试验和BBB运动功能评分，观察大鼠后肢运动功能的恢复情况。第22天将所有实验大鼠处死后取出脊髓损伤标本，进行组织学检查。结果45只实验鼠中符合设计要求的共40只，其中三七总皂甙（Panax notoginseng saponins，PNS）组13只，空白对照组14只，甲基强的松龙（Methylprednisolone，MP）组13只。三七总皂甙组大鼠的BBB评分及斜板测定均优于对照组，两者之间的差异有统计学意义（P〈0．05）。电镜下三七总皂甙组大鼠脊髓损伤部位可见神经元核周体和神经纤维修复再生。对照组大鼠脊髓损伤区神经元胞体和轴突的超微结构发生明显的变性。结论三七总皂甙可以改善脊髓损伤区的组织结构并促进大鼠脊髓损伤后运动功能的恢复．     

Effects of Co-grafts Mesenchymal Stem Cells and Nerve Growth Factor Suspension in the Repair of Spinal Cord Injury

Endogenous repair ability of mammalsisli mit-ed after the damage of central nervous system.It isdifficult to produce the new neurons for the dam-aged adult central nervous system,and neither canthe damaged systemstart the functional axonal re-generation. At present ,a good many methods arebelieve to be able toi mprove the damagedlocal mi-croenvironment , such as cell transplantation andprovision of exogenous neurotrophic factors ,whichare ai med at promoting the regeneration of thedamaged spin…     

神经前体细胞移植治疗大鼠急性脊髓损伤的功能评价

目的：神经前体细胞移植治疗大鼠脊髓损伤的行为变化及功能评价。方法：采用改良A11en法建立大鼠脊髓损伤模型，术后9d，实验组脊髓损伤局部注射移植永生化神经前体细胞系G3。采用只注射培养液和不作治疗处理作为对照组。细胞移植后，采用BBB评分进行功能评价，每周评分1次，检测脊髓损伤大鼠后肢运动功能的改变。分别在细胞移植的第8周和第12周进行运动诱发电位的神经电生理检查，检测脊髓的传导功能。结果：实验组移植水生化神经前体细胞后，其BBB评分和对照组相比差异无显著性；但运动诱发电位与对照组相比明显提高。结论：永生化神经前体细胞移植可显著提高大鼠急性损伤脊髓的传导功能恢复。     

神经干细胞移植对大鼠脊髓损伤后GDNF基因表达的影响及意义

目的:探讨神经干细胞(NSC)移植对大鼠脊髓损伤后胶质细胞源性神经营养因子(GDNF)表达的影响及其意义。方法:NSC提取自新生Wistar大鼠的海马区,经培养、鉴定。制作大鼠脊髓损伤(SCI)模型,于伤后第7d移植NSC。实验分为3组:NSC移植组(A组)、DMEM填充组(B组)、正常对照组(C组)。应用RT-PCR法和免疫组化法观察细胞移植后不同时间点GDNF基因的表达变化。结果:RT-PCR结果分析,移植术后第1,3,5d,A组GDNF mRNA的表达量明显高于B组,差别有显著性意义(P<0.05)。组化结果分析,移植术后第7,14,28d GDNF的表达量明显高于B组,差别有显著性意义(P<0.05)。结论:NSC在移植后可上调神经营养因子GDNF基因的表达,是修复脊髓损伤的机制之一。     

嗅神经鞘细胞移植治疗实验性脊髓损伤的研究

目的:观察移植体外培养的嗅神经鞘细胞(OEC)对大鼠脊髓左半侧横断伤的治疗作用。方法:将应用改良Nash法培养的OECs移植到成年大鼠T10脊髓左半侧横断处,8周后分别采用改良Tarlov法运动学功能评分、辣根过氧化物酶(HRP)顺行示踪、透射电镜观察、P75免疫组织化学染色及HE染色等方法,观察动物的运动功能、脊髓再生的轴突和髓鞘、OEC的存活和脊髓损伤程度。结果:8周时治疗组运动学功能评分高于对照组(P<0.05);治疗组再生轴突穿越损伤区,对照组则无再生轴突穿越;超微结构显示治疗组轴突数量多于对照组,且髓鞘的完整性强于对照组,OEC表现为星形胶质细胞样和雪旺氏细胞样两种,包绕轴突髓鞘;免疫组化染色显示移植后8周OECs仍然存活,在损伤区均匀、散在分布;损伤后8周脊髓损伤区有胶质瘢痕及空洞形成。结论:移植的嗅神经鞘细胞可促进大鼠运动功能的恢复、脊髓轴突的再生和髓鞘的重塑。