Effects of magnesium sulfate on neuron apoptosis and expression of caspase- 3， bax and bcl-2 after cerebral ischemia-reperfusion injury

Objective To investigate the effects of magnesium sulfate on neuron apoptosis and the expressions of caspase-3,bax and bcl-2 after cerebral ischemia-reperfusion injury. Methods Thirty-six gerbils were randomly divided into three groups: Sham-operation group (So, n=12), ischemia-reperfusion group (I-R, n=12) and magnesium sulfate group (Ms, n=12). The neuron apoptosis was detected by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-fluorescence nick end labeling (TUNEL stain), and the protein expressions of caspase-3, bax and bcl-2 were detected by immunohistochemisty stain.Results Apoptotic neurons and the expressions of caspase-3 and bax were significantly increased in I-R and Ms groups, compared with those in So group. Apoptotic neurons and the expressions of bax and caspase-3 in Ms group were significantly less than those in I-R group. There was no significant difference in the expression of bcl-2 among three groups.Conclusions Magnesium sulfate decreases neuron apoptosis after cerebral ischemia-reperfusion injury, which may be related with the suppressed expressions of caspase-3 and bax.     

Morphological study of fetal neocortical transplant grafted to the cerebral corresponding area in young rats. Differentiation of immature neurons and reciprocal connections of fibers between graft-host brain.

The fetal neocortical transplant (E15-17 days gestation) of Wistar rat was grafted to the corresponding neocortical region (frontal-parietal lobe) of the same strain in young rats (4-5 weeks old). On the 7th, 15th, 30th, 60th, 150th day after transplantation, the sections cut through the middle area of graft-ost brain were examined by HE, Nissl, Glees stain, immunohistochemical technique for GFAP and NF, Nissl, Glees stain, immunohistochemical technique for GFAP and NF, acetylcholinesterase (AChE) histochemistry as well as horseradish peroxidase (HRP) retrograde tracing with light microscope. Some of the sections were also examined with TEM. The result showed that most immature neurons within the graft can survive, grow, differentiate and mature, and are similar to the structure of the neocortical neurons of host brain. This study also provides patterns of integration of the interface between graft-host brain varying with the proliferation of reactive astrocyte as well as graft-host reciprocal connectio     

Experimental study on dynamic regulation of acetylcholine in striatum of rat parkinson disease model and behavior observation

In order to explore the role of acetylcholine in the pathogenesis of Parkinson’s disease (PD),the changes in the concentration of acetylcholine (Ach) in the striatum,the apoptosis of substantia nigra cells,the ultrastructure and the changes of Nissl cells in rats during the morbidity of PD,and the corresponding behaviors in rats with PD were observed.Rat PD model was established by using the modified Thomas method.Eighty-one rats were randomly divided into normal control,sham operation and PD groups and their behavior features were observed at post-operative day (POD) 7,14 and 21 as three subgroups (n=9 each).The concentration of Ach in the striatum was determined by using high-performance liquid chromatography.The apoptosis of substantia nigra cells was assayed by using TUNEL method.The ultrastructural changes in the substantia nigra were observed under the electron microscopy,and the survival of neurons in the substantia nigra area was examined by using Nissl staining.In PD group at POD 7 to 21,the damage in the substantia nigra area was gradually aggravated,the concentration of Ach,apoptosis rate and turns of rotation were gradually increased,and the number of Nissl cells was gradually reduced over the time as compared with the normal control and sham operation groups (all P<0.05).It was concluded that there exist dynamic changes in Ach concentration,ethology and apoptosis of the substantia nigra cells during the morbidity of PD,suggesting the contribution of apoptosis to the morbidity of PD,and critical role of Ach in the pathogenesis of PD.     

Effect of Antisense FosB and CREB on the Expression of Prodynorphin Gene in Rats with Levodopa-induced Dyskinesias

The effects of antisense FosB and CREB intra-striatum injection on the expression of prodynorphin (PDyn) gene in striatal neurons of Levodopa-induced dyskinesias (LID) rats with Parkinson disease (PD) were explored. PD model in rats was established by 6-OHDA microinjection stereotaxically. The rats were treated with chronic intermittent Levodopa celiac injection for 28 days to get the LED rats. Antisense FosB and cAMP response element-binding protein (CREB) were injected into striatum of all rats respectively. In situ hybridization was used to measure the changes in the expression of PDyn mRNA in striatum and behavior changes were observed. The results showed after administration of antisense FosB, abnormal involuntary movement (AIM) was decreased and the expression of PDyn mRNA in striatum was increased in LID rats as compared with sense FosB group (P<0.01, respectively). As compared with the control group, the expression of PDyn mRNA in striatum was decreased by antisense CREB-treated LID group (P<0.01) and compared with sense CREB treated LID group, antisense CREB-treated LID group showed no changes in AIM scores and the expressions of PDyn mRNA (both P>0.05). In conclusion, FosB protein, which replaced the CREG, could regulate the expression of PDyn mRNA and play critical role in the pathogenesis of LID.     

Effect of Resveratrol on Motor Dysfunction in Unilateral 6-hydroxydopamine Parkinson’s Model Rats and its Underlying Mechanisms

Objective：The present study was designed to investigate the effect of resveratrol（Res） on the motor function of Parkinson’s model rats induced by 6-hydroxydopamine （6-OHDA） and to explore its underlying mechanism. Methods：After a week of adaptive feeding,50 male Sprague-Dawley （SD） rats were randomly divided into fi ve groups：sham-operated group,normal group （Res,30 mg·kg-1）,model group （6-OHDA,8 μg）,6-OHDA+Res low-dose group （15 mg·kg-1,6-OHDA+Res high-dose group （30 mg·kg-1）. 6-OHDA 8 μg （2 μg·μL-1） were injected into the substantia nigra of the rats to establish the model of dopaminergic neuronal damage,while the rats of sham group were injected with volume-matched saline with 0.2% Vitamin C.Rats were pretreated with Res for 1 day before 6-OHDA treatment. Model and sham groups were administered with volume-matched vehicle for 36 days.Rotarod test was applied to evaluate motor function of rats on 7 th,14 th and 21 th day after surgery,open fi eld experiment and grid-walking test applied on 33 th and 35 th day,respectively. Then the rats were sacrificed.Immunohistochemistry was used to detect the number of TH-positive cells in substantia nigra pars compacta （SNc）;the protein expression of TH,Bax,Bcl-2,pro-caspase-3, active-caspase-3,p-PDK1 and p-Akt in midbrain were detected by Western blot. Results：The body weight,motor function,number of dopaminergic neurons in SNc and the protein expression of TH in midbrain of model group were significantly decreased compared with sham group;the protein of Akt phosphorylation levels were decreased while it showed no effect on PDK1,and the expression of apoptosis-related proteins Bax/Bcl-2,active-caspase-3 were significantly increased,pro-caspase-3 decreased. However,compared with model,the body weight,motor function,number of dopaminergic neurons in SNc and the protein expression of TH in midbrain of Res high-dose group were markedly increased;the protein of Akt phosphorylation levels were increased while it showed no effect on PDK1,the protein level of BDNF and TrkB were signifi cantly decreased and the expression of apoptosis-related proteins Bax/Bcl-2,active-caspase-3 were significantly decreased,and pro-caspase-3 were increased.Conclusion：Under the experimental conditions,6-OHDA-induced motor dysfunction and apoptosis in dopaminergic neuronal cells of rats is signifi cantly attenuated by Res,and its potential mechanism may be related to up-regulation of Akt phosphorylation at Ser473 and inhibit the expression of apoptosisrelated proteins.     

Recombinant AAV-mediated Expression of Human BDNF Protects Neurons against Cell Apoptosis in Aβ-induced Neuronal Damage Model

The human brain-derived neurotrophic factor (hBDNF) gene was cloned by polymerase chain reaction and the recombinant adeno-associated viral vector inserted with hBDNF gene (AAV-hBDNF) was constructed. Cultured rat hippocampal neurons were treated with Aβ25-35 and se- rued as the experimental Aβ-induced neuronal damage model (AD model), and the AD model was infected with AAV-hBDNF to explore neuroprotective effects of expression of BDNF. Cell viability was assayed by MTT. The expression of bcl-2 anti-apoptosis protein was detected by immunocyto- chemical staining. The change of intracellular free Ca ion ([Ca2 ]i) was measured by laser scanning confocal microscopy. The results showed that BDNF had protective effects against Aβ-induced neu- ronal damage. The expression of the bcl-2 anti-apoptosis protein was raised significantly and the bal- ance of [Ca2 ]i was maintained in the AAV-hBDNF treatment group as compared with AD model group. These data suggested that recombinant AAV mediated a stable expression of hBDNF in cul- tured hippocampal neurons and resulted in significant neuron protective effects in AD model. The BDNF may reduce neuron apoptosis through increasing the expression of the bcl-2 anti-apoptosis protein and inhibiting intracellular calcium overload. The viral vector-mediated gene expression of BDNF may pave the way of a novel therapeutic strategy for the treatment of neurodegenerative dis- eases such as Alzheimer’s disease.     

Effect of fusion protein TAT and heme oxygenase-1 on liver sinusoidal endothelial cells apoptosis during preservation injury

Background Proteins or peptides can be directly transferred into cells when covalently linked to protein transduction domains （PTDs）. TAT is one of the most widely studied PTDs. The effect of fusion protein TAT and heme oxygenase-1 （HO-1） on liver sinusoidal endothelial cells （SECs） apoptosis during cold storage is unknown. The present study aimed to determine whether fusion protein TAT-HO-1 would transduce efficiently into liver during cold storage, and, if so, to determine whether TAT-HO-1 would attenuate SECs apoptosis during preservation injury in rat. Methods Livers of Sprague-Dawley rats were harvested and randomly assigned to group 1 （HTK solution） and group 2 （HTK solution containing TAT-HO-1 fusion protein） according to the type of the preservation solution. The transduction efficiency of TAT-HO-1 was examined and the impairment of SECs was assessed during the period of cold storage followed by 1 hour of reperfusion. Results TAT-HO-1 can transduce efficiently into liver during cold storage. A significantly lower apoptotic index of SECs was observed in group 2, at 6, 12 and 18 hours of cold storage after 1 hour reperfusion, when compared with group 1. TAT-HO-1 reduced HA and ET levels in liver at each time point. Both Bcl-2 and Bax protein were expressed in hepatocytes and SECs at the periphery of the sinusoidal space. Moreover, higher Bcl-2 expression and lower Bax expression were observed in group 2. Conclusions TAT-HO-1 can transduce efficiently into rat livers and shows a protective effect on SECs by attenuating apoptosis during cold ischemia/reperfusion injury. Protein transduction will be a novel therapeutic strategy to reduce the risk of preservation injury in liver transplantation.     

Effects of extract of Ginkgo biloba with venlafaxine on brain injury in a rat model of depression

Background Recent studies have indicated that chronic stress may give rise to brain damage,which is related to the genesis of depression. The purpose of this study is to investigate the effects of extract of Ginkgo biloba (EGb) and venlafaxine on depression. Methods Rats were treated with chronic and comprehensive stress to create a depression model. Immunohistochemistry was used to detect the expression of brain-derived neurotrophic factor (BDNF) in the hippocampal CA3 neurons of rats treated with different drugs. Behavioral changes of these rats were also examined.Results The expression of BDNF in the hippocampal CA3 neurons of the depression model decreased with a reduction in exploring behavior and a significant increase in fecal production. The expression of neuron nitricoxide synthase (nNOS) protein also increased in the rats compared to normal controls. The rats treated with EGb and venlafaxine showed an increase in expression of BDNF and exploring behavior compared to untreated rats, but a decrease in nNOS and fecal production. Conclusions Rats sustain damage to the brain after being subjected to chronic and comprehensive stress. Our research has indicated that combined EGb with venlafaxine enhances the protection of neurons and decreases damage to the brain, while relieving the side effects of synthetic antidepressants.     

Combined therapy of methylprednisolone and brain-derived neurotrophic factor promotes axonal regeneration and functional recovery after spinal cord injury in rats

Objective To investigate the effects of combination therapy with methylprednisolone (MP) and brain-derived neurotrophic factor (BDNF) on axonal remyelination and functional recovery after spinal cord injury in rats. Methods Forty-five rats were randomly divided into three groups: Group A received MP and BDNF; group B received MP and cerebrospinal fluid (CSF); and group C received CSF only. Contusion injury to adult rat spinal cord was produced at the T［10］ vertebra level followed by immediate intravenous MP or CSF, and was thereafter infused intrathecally with BDNF or CSF for 6 weeks. Axonal remyelination and functional recovery was observed using RT-PCR, immunohistochemistry and open field locomotion. Results An increase of 28.4%±2.3% in the expression of proteolipid protein (PLP) gene, an endogenous indicator of axonal remyelination, was demonstrated in group A 24 hours after injury. Ten weeks later, there were significant decreases in hematogenous inflammatory cellular infiltration in groups A and B compared to C (P&lt;0.05). Concomitantly, a significant amount of axonal remyelination was observed in group A compared to groups B and C (P&lt;0.05). Furthermore, combination therapy using MP and BDNF in group A resulted in stimulation of hindlimb activity as well as improvement in the rate of functional recovery in open field locomotion (P&lt;0.05). Conclusions Combined therapy of MP and BDNF can improve functional recovery through mechanisms that include attenuating inflammatory cellular infiltration and enhancing axonal remyelination at the injury site. Such a combination may be an effective approach for treatment of spinal cord injury.     

STUDY ON EFFECTS OF QUERCETIN ON PML GENE AND PROTEIN IN LEUKEMIA CELL LINES

Objective To investigate the effect of quercetin on PML gene and protein expression andlocalization in leukemia cell lines. Methods Cell morphology was assayed by Wright's stain and fluorescence stain, and PML mRNA expression by RT-PCR , PML protein localization by immuno-fluorescence. Results NB4 and HL-60 cells differentiated morphologically after treatment with all-trans-retinoic acid (ATRA) while K562 cells did not differentiate. Typical apoptosis was found in each cell line after treatment with quercetin. Immuno-fluorescence analysis showed , after treatment with ATRA , the fusion protein disappeared in NB4 cells and PML protein relocated , while HL-60 and K562 cells had no difference from control cells. After treatment with quercetin, the fusion protein disappeared in NB4 cells, PML protein relocated, then degraded. In HL-60 cells and K562 cells, PML protein also located and then degraded . The expression of PML mRNA was not changed in all three cell lines after treatment with ATRA or quercetin. C     

不同强度减重步行训练对脊髓损伤模型大鼠脊髓组织中TrkB和BDNF蛋白表达水平的影响及其对运动功能恢复的促进作用

目的：观察减重步行训练（BWSTT）对脊髓损伤（SCI）大鼠脊髓组织中受体酪氨酸蛋白激酶B （TrkB）及脑源性神经营养因子（BDNF）蛋白表达水平和运动功能的影响,并探讨其可能的作用机制。方法：50只成年雄性SD大鼠随机分为假手术组、SCI组、BWSTT-A组（低强度训练）、BWSTT-B组（中强度训练）和BWSTT-C组（高强度训练）,每组10只。应用自制的打击器制备SCI模型。假手术组大鼠仅行椎板切除术暴露硬脊膜,不予打击,直接缝合,术后不给予任何治疗;SCI组大鼠造模后不给予任何治疗;BWSTT组大鼠在SCI后给予康复锻炼,3组大鼠步行速度分别为7、15和21 cm·s^-1。在造模后35 d采用Basso、Beattie和Bresnahan （BBB）评分评定SCI大鼠后肢功能恢复情况,免疫蛋白印记法检测各组大鼠脊髓组织中TrkB和BDNF蛋白表达水平,尼氏染色法检测各组大鼠脊髓尼氏小体的形态和数量。结果：与SCI组比较,BWSTT-B组和BWSTT-C组大鼠BBB评分升高（P<0.01）;与BWSTT-A组比较,BWSTT-B组和BWSTT-C组大鼠BBB评分升高（P<0.01）。免疫蛋白印记法检测,与假手术组比较,SCI组大鼠脊髓组织中TrkB蛋白表达水平降低（P<0.01）;与SCI组比较,BWSTT-B组和BWSTT-C组大鼠脊髓组织中TrkB蛋白表达水平升高（P<0.01）;与假手术组比较,SCI组大鼠脊髓组织中BDNF蛋白表达水平降低（P<0.01）;与SCI组比较,BWSTT-B组和BWSTT-C组大鼠脊髓组织中BDNF蛋白表达水平均升高（P<0.01）。尼氏染色法检测,与SCI组比较,BWSTT组细胞尼氏小体数量较多,细胞形态较好。结论：中和高强度的BWSTT可在一定程度上促进SCI大鼠运动功能恢复,其机制可能与上调脊髓组织中TrkB和BDNF蛋白的表达有关。     

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.     

内毒素预处理激活大鼠急性脊髓损伤Nrf2蛋白抑制Caspase-3的表达

目的 研究大鼠急性脊髓损伤及经内毒素预处理后损伤脊髓中转录因子Nrf2及凋亡蛋白Caaspase-3的表达.方法SD大鼠132只,随机数字表法分为假手术组、模型组和LPS预处理组.采用改良Allen's打击法制作SD大鼠急性脊髓损伤(acute spinal cord injury,ASCI)模型,在术后1、3、5、7...     

振荡电场对脊髓损伤大鼠β-catenin蛋白表达和神经元再生的影响

目的 观察振荡电场对脊髓损伤大鼠β-catenin蛋白表达规律和神经元再生的影响.方法 60只SD大鼠采用改良Allen′s打击法建立脊髓损伤模型,随机分为对照组和实验组.实验组施加振荡电场干预,对照组只置入振荡电场刺激器而不给予干预.建模成功后分别在3、7、14 d取大鼠脊髓,行HE染色观察脊髓大体形态变化,采用Western blot和免疫组化技术检测脊髓中β-catenin蛋白表达规律,行免疫荧光检测观察神经元变化情况,并在取材前对两组大鼠行Basso-Beattle-Bresnahan(BBB)行为学评分.结果 Western blot和免疫组化结果均显示,3 d时两组脊髓灰质内β-catenin蛋白均高表达,随时间延长表达量逐渐减少,同时实验组在各时间点β-catenin蛋白表达量均高于对照组(P<0.05).神经元的表达在3~14 d时呈现递增的趋势,但实验组神经元在表达数量上明显优于对照组,同时细胞形态更加规则.两组BBB评分3、7 d时差异无统计学意义,而14 d时,实验组BBB评分明显高于对照组(P<0.05).结论 振荡电场可以提高大鼠脊髓损伤区域β-catenin蛋白表达量,并促进神经元再生,从而改善受损脊髓神经功能.     

慢性脊髓损伤组织学变化及神经细胞的实验研究凋亡

目的 :建立慢性压迫性脊髓损伤的动物模型 ,观察组织病理学变化及细胞的凋亡。方法 :自制压迫装置 ,造成兔 L2脊髓的慢性压迫。尼氏染色观察一般组织病理变化 ,原位末端标记方法 (TU NEL)标记凋亡的细胞。结果 :实验组压迫区白质神经胶质细胞增生 ;后索较重 ,侧索及前索较轻 ;神经元尼氏小体淡染、消失 ;神经元萎缩 ,脱失 , 板层明显。标记阳性细胞为神经胶质细胞 ,各索内均可见到 ,后索及侧索明显。灰质中阳性细胞数量较少 ,为神经胶质细胞 ,主要在 、 板层。相邻段病变次之 ,远段接近正常。对照组与实验组相比细胞凋亡数大为减少 (P<0 .0 5 ) ,与正常组比较区别不大 (P>0 .0 5 )。在各组每段都未观察到阳性标记神经元。结论 :机械性压迫是病理变化的主要因素 ,也是细胞凋亡的主要原因 ;神经胶质细胞的凋亡可能是继发病变的机制之一。     

益肾养髓方对脊髓型颈椎病大鼠脊髓中神经营养因子表达的影响及其神经修复作用研究

背景　骨关节退行性改变压迫脊髓所致的脊髓型颈椎病（CSM）与脊髓急性损伤在病理特点及治疗策略方面存在差异,中医药治疗退行性CSM有着独特优势,临床应用广泛,但脊髓慢性压迫相关的治疗机制研究较少。目的　研究益肾养髓方对脊髓慢性压迫大鼠脊髓（C5~7）神经生长因子（NGF）、神经营养因子3（NT3）、胶质细胞源性神经营养因子（GDNF）的mRNA表达水平影响及NGF的蛋白表达和分布情况,探讨益肾养髓方促进CSM神经功能修复的作用机制。方法　2019年1月选取SPF级雌性SD大鼠96只,其中72只大鼠采用吸水膨胀材料聚乙烯醇丙烯酰胺互穿网络水凝胶（由北京师范大学化学学院提供）压迫脊髓的方法进行造模,余24只大鼠假手术（假手术组）。造模成功的大鼠随机分为模型组（n=24）、中药高浓度组（n=16）、中药中浓度组（n=16）、中药低浓度组（n=16）。中药灌胃的各组按照对应浓度进行灌胃（大鼠灌胃给药剂量采用体表面积系数换算系数6.3计算,高浓度为16.74 g•kg-1•d-1、中浓度为8.37 g•kg-1•d-1、低浓度为4.19 g•kg-1•d-1）,药液浓缩后以1 ml/100 g体积灌胃给药,模型组及假手术组灌服等量（1 ml/100 g）0.9%氯化钠注射液,1次/d。分别于术后2、4、6、8、10周时,评价各组大鼠运动功能指数评分（BBB评分）;术后2、6、10周时,尼氏染色法观察大鼠脊髓前角正常神经元的尼氏体分布,实时荧光定量逆转录聚合酶链式反应（RT-qPCR） 法检测大鼠脊髓营养因子NGF、NT3、GDNF的 mRNA表达水平、免疫组织化学分析NGF脊髓前角区蛋白表达及分布情况。结果　（1）术后2周,假手术组BBB评分高于模型组、中药高浓度组、中药中浓度组和中药低浓度组（P<0.05）;术后4周,假手术组BBB评分高于模型组、中药高浓度组、中药中浓度组和中药低浓度组（P<0.05）;术后6周,假手术组BBB评分高于模型组、中药高浓度组、中药中浓度组和中药低浓度组（P<0.05）,模型组BBB评分低于中药高浓度组（P<0.05）,中药高浓度组BBB评分高于中药中、低浓度组（P<0.05）;术后8周,假手术组BBB评分高于模型组、中药高浓度组、中药中浓度组和中药低浓度组（P<0.05）,模型组BBB评分低于中药高浓度组（P<0.05）,中药高浓度组BBB评分高于中药中、低浓度组（P<0.05）;术后10周,假手术组BBB评分高于模型组、中药高浓度组、中药中浓度组和中药低浓度组（P<0.05）,模型组BBB评分低于中药高、中浓度组（P<0.05）,中药高浓度组BBB评分高于中药中、低浓度组（P<0.05）。（2）术后2周,假手术组脊髓前角运动神经元形态正常,可见大量虎斑状尼氏体,丰富饱满;模型组脊髓前角神经元细小,形态为圆形,分布稀疏,胞内尼氏体溶解减少甚至消失;在术后6、10周时,中药高、中浓度组神经元虽有一定程度损伤,但细胞形态丰满、可见细胞内虎斑状尼氏体;中药低浓度组可见少量空泡,神经元细胞分布略稀疏,单个细胞内尼氏体数目比中药高、中浓度组含量少。术后2周,假手术组正常神经元数目多于模型组（P<0.05）。术后6周,假手术组正常神经元数目多于模型组、中药中浓度组和中药低浓度组（P<0.05）,模型组正常神经元数目少于中药高浓度组（P<0.05）,中药高浓度组正常神经元数目多于中药低浓度组（P<0.05）。术后10周,假手术组正常神经元数目多于模型组、中药低浓度组（P<0.05）,模型组正常神经元数目少于中药高浓度组（P<0.05）。（3）术后6周,中药高浓度组NGF mRNA表达水平高于假手术组、模型组和中药低浓度组（P<0.05）,中药高浓度组NT3 mRNA表达水平高于模型组（P<0.05）,中药高浓度组GDNF mRNA表达水平高于假手术组、模型组和中药中、低浓度组（P<0.05）。（4）假手术组和模型组中脊髓前角的神经元细胞NGF染色程度较浅,分布稀疏,中药高、中浓度组大鼠的脊髓前角神经元NGF染色较明显,细胞形态完整。术后6周,中药高浓度组NGF平均积分光密度值高于假手术组和模型组（P<0.05）。结论　益肾养髓方可能通过增加脊髓中NGF、NT3、GDNF的mRNA表达水平,改善CSM大鼠的四肢运动功能,保护脊髓前角中正常运动神经元,从而达到促进神经修复的效果。     

针刺对大鼠脊髓损伤后脊髓前角运动神经元功能的影响

目的探讨针刺对脊髓损伤(SCI)大鼠前角运动神经元功能恢复的影响。方法成年雄性SD大鼠60只,改良Allen法压迫致伤T8、T9,随机分为实验组和对照组,伤后分别给予电针刺激大鼠双下肢足三里和悬钟、伏兔和三阴交穴,取治疗2,4,6周伤段脊髓进行PCR扩增和组织切片。利用RT-PCR技术检测伤区脊髓胶质源性神经营养因子(GDNF)mRNA基因体内表达的变化;应用尼氏染色、酶组织化学染色方法观察大鼠SCI后伤区脊髓前角运动神经元存活的数目和乙酰胆碱酯酶(AChE)的变化;采用斜板试验和BBB评分法观察大鼠后肢运动功能恢复情况。结果实验组较对照组AChE活性显著增加(P<0.01);实验组脊髓前角大、中型神经元的数目较对照组明显增加(P<0.05);实验组GDNF mRNA基因体内表达较对照组明显增加(P<0.01);大鼠SCI 3周后针刺治疗组后肢运动功能评分均明显高于对照组(P<0.05)。结论针刺治疗对脊髓损伤后前角运动神经元的功能恢复有一定的促进作用。     

大鼠脊髓T3节段全横断后损伤节段神经元超微结构的观察

目的：观察大鼠脊髓T3节段全横断后损伤节段神经元超微结构的变化。方法：48只大鼠随机分为假手术组和脊髓T3完全横断损伤1d组、2d组、7d组、14d组、21d组,每组8只。各组大鼠BBB运动功能评分后取损伤节段脊髓,透射电镜观察脊髓神经元超微结构的变化。结果：脊髓损伤（SCI）各组大鼠的BBB评分明显低于假手术组（P ＜0.01）;随着损伤时间的延长,SCI各组大鼠的BBB评分逐渐升高（P ＜0.01）。电镜下观察,大鼠脊髓神经元在损伤后2d病理变化最为严重,表现为神经元明显肿胀,线粒体等细胞器严重受损,核固缩,染色质凝集;损伤后7d时,脊髓神经元的病理变化有所减轻;损伤后21d,脊髓神经元的病理变化明显减轻,甚至接近正常。结论：大鼠脊髓损伤后2d脊髓神经元的病理变化最为严重,后逐渐减轻。     

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。     

黄芪注射液对大鼠急性脊髓损伤的神经保护作用及机制研究

目的 基于细胞凋亡Fas和TRAIL死亡受体信号通路探讨黄芪注射液对大鼠急性脊髓损伤(SCI)的神经保护作用及机制。方法 40只健康的雄性SD大鼠随机分为假手术组,SCI模型组,黄芪注射液低、中、高剂量(1、2、4 mL·kg^-1)组,每组8只。采用改良的重物打击法构建大鼠急性SCI模型;按照BBB评分和Rivlin斜板实验评价大鼠运动功能;苏木精-伊红(Hematoxylin-eosin, HE)染色检测脊髓组织病理变化;尼氏染色法检测脊髓神经元细胞损伤程度;高通量转录组测序分析差异表达基因;qPCR验证基因转录水平的表达量;利用TUNEL试剂盒检测各组脊髓细胞凋亡情况;Western blot检测凋亡通路关键蛋白表达水平。结果 BBB评分和斜板试验结果显示,与假手术组比较,模型组大鼠表现出明显的运动功能障碍;HE染色显示模型组脊髓组织病理病变严重;模型组尼氏染色着色较浅,神经元细胞损伤严重;与假手术组比较,模型组脊髓中4 597个基因差异表达,Fas、TRAIL、Caspase-3、Caspase-8、Caspase-9和Bax蛋白表达显著上调(P<0....