Noggin参与海人酸损伤后成年大鼠海马颗粒下区颗粒细胞增殖

目的 探讨侧脑室注射海人酸(KA)致大鼠海马损伤后Noggin的表达变化及其与颗粒细胞增殖的关系.方法 健康雄性SD大鼠32只采用随机数字表法分为实验组(16只)及对照组(16只).对照组又分为生理盐水对照组和空白对照组,各8只.实验组大鼠侧脑室注射KA,生理盐水对照组注射等剂量生理盐水.空白对照组不作处理.侧脑室注射KA 1周内,尼氏染色检测海马神经元的丢失.免疫荧光染色与原位杂交的方法检测海马齿状回BrdU标记细胞与Noggin mRNA阳性细胞的变化.结果 在侧脑室注射KA致海马损伤后1周,海马CA3、CA4区神经元丢失明显.与生理盐水对照组比较,实验组海马齿状回BrdU阳性细胞升高,差异有统计学意义(P=0.006),其中注射侧较对侧更为明显.海马Noggin mRNA阳性细胞在第3天时升高,第7天时下降.结论 侧脑室注射KA致海马损伤后.成年大鼠海马齿状回颗粒细胞异常增殖可能与Noggin表达波动有关.     

海人酸损伤后海马神经干细胞的异常分布及骨形成蛋白4的表达

目的探讨海人酸(kainic acid,KA)侧脑室注射致大鼠海马损伤后,大鼠海马的异位神经干细胞分布特点及骨形成蛋白4(bone morphogenetic proteins-4,BMP4)的表达。方法侧脑室注射KA3d￣2周后,免疫组化检测海马神经元的丢失情况(NeuN染色)和海马齿状回Nestin阳性细胞的分布情况,原位杂交检测同期BMP4-mRNA阳性细胞的分布。结果KA注射后1周,注射侧海马CA3、CA4区神经元丢失明显且在整个实验观察阶段均存在。KA注射2周后,在海马齿回门区出现大量异常分布的Nestin阳性细胞,这些细胞成团分布,同期可观察到BMP4-mRNA阳性细胞在该部位有较多分布。KA注射4周后,海马齿回门区Nestin阳性细胞数量增多,突起延长且突起数量增多。结论KA侧脑室注射致大鼠海马损伤后,海马齿状回颗粒细胞异常增殖和迁移,主要分布在海马齿回门区,可能与BMP4在该区的过表达有关。     

烟碱上调大鼠脑纹状体多巴胺D1受体mRNA表达诱导其行为改变

目的　 通过观察烟碱对大鼠脑纹状体D1,D2 受体mRNA表达的影响 ,研究烟碱诱导大鼠行为改变的可能机制 ,以进一步探讨烟碱对帕金森病具有保护效应的作用机理。 方法 SD大鼠 2 4只 ,随机分为生理盐水组(12只 )、烟碱组 (12只 )。分别给予生理盐水、烟碱 4mg/kg·d,2次 /d ,共 14d。每次注射药物后 0 .5h观察大鼠行为活动 ,并于末次注射药物后 0 .5h处死动物 ,快速分离纹状体 ,采用RT PCR方法检测大鼠纹状体D1,D2 受体mRNA的表达。结果 烟碱组大鼠于用药后第 3天 ,出现走动增多 ,易激惹 ,定型活动明显 ,并于第 714天达到高峰。在大鼠纹状体内 ,烟碱组D1受体mRNA表达比对照组上升 2 3% (分别为 98.6 3± 1.13,6 5 .2 9± 1.4 5 ,P <0 .0 1) ,两组D2 受体mRNA的表达无显著性差异 (P >0 .0 1)。 结论 烟碱可能通过上调大鼠纹状体D1受体mRNA的表达而诱导大鼠理毛、张口等行为改变 ;烟碱可能有部分D1受体激动样作用。     

深部脑刺激丘脑底核治疗帕金森病大鼠脑中钙调蛋白的变化

目的 研究慢性高频电刺激帕金森病(Parkinson's disease,PD)大鼠丘脑底核治疗PD的机制.方法 通过6-羟基多巴立体定向注射至大鼠中脑前脑束建立偏侧PD动物模型,对造模成功的PD大鼠模型丘脑底核进行高频电刺激,观察高频电刺激对PD大鼠行为的影响,并用蛋白印迹法检测纹状体酪氨酸羟化酶(TH)、钙调蛋白Calbindin-28和突触前膜囊泡蛋白(synaptophysin)的表达情况.此外,对接受慢性高频电刺激的6-羟基多巴损伤纹状体双侧PD大鼠的脑片进行免疫组化染色,检测黑质Calbindin-28和突触前膜囊泡蛋白的表达情况.结果 (1)高频电刺激偏侧PD大鼠丘脑底核可使阿朴吗啡诱导的旋转行为减少31%;(2)偏侧PD大鼠损伤侧纹状体内已无TH表达,慢性高频电刺激同侧丘脑底核对纹状体TH缺失无逆转,但增加健纹状体内TH表达量78.6%±9.5%;(3)偏侧PD大鼠损伤侧纹状体内Calbindin-28表达量增加75.4%±15.0%,慢性高频电刺激使其表达量减少43.0%±7.1%;(4)慢性高频电刺激亦显著抑制双侧PD大鼠黑质Calbindin-28表达:假手术大鼠、PD大鼠以及慢性高频电刺激后PD大鼠黑质致密部Calbindin-28阳性神经元分别为74.5±10.2、75.7±15.6和33.1±7.8;(5)慢性高频电刺激未影响黑质和纹状体内突触前膜囊泡蛋白的表达.结论 深部脑刺激治疗PD的机制与调节黑质和纹状体内钙调蛋白Calbindin-28和TH表达量有关.     

神经干细胞生存因子在大鼠脊髓损伤前后的表达变化(英文)

目的观察大鼠脊髓损伤后干细胞来源的神经干细胞生存因子(SDNSF) mRNA在大鼠正常和损伤脊髓的表达变化,以及SDNSF的表达与Ⅵ类中间丝蛋白的表达之间的关系。方法按改良的Allen重物打击法制备大鼠脊髓损伤模型,采用RT-PCR、原位杂交方法,观察SDNSF mRNA在大鼠脊髓中的表达位置及在损伤脊髓中的表达变化。应用免疫组化的方法,显示脊髓中nestin 的表达。结果 RT-PCR检测SDNSF mRNA在正常大鼠脊髓中的表达,损伤后4天SDNSF 的mRNA表达上升,损伤8天到达高峰,此后SDNSF 的mRNA表达逐渐减少,到16天恢复到正常水平;脊髓切片原位杂交结果发现SDNSF的 mRNA 阳性细胞主要分布于脊髓灰质细胞中,可能是神经元细胞,结果表明正常脊髓可表达SDNSF;脊髓损伤后8天,原位杂交显示SDNSF阳性细胞明显增多。同时与此切片相邻层面的切片免疫组化证实nestin阳性细胞增殖、变大、向周围发出突起,但这些阳性细胞在分布上与SDNSF无关。结论 (1) SDNSF在脊髓中表达于灰质,脊髓损伤后SDNSF的 mRNA表达随时间发生变化。(2)随着脊髓损伤的修复,nestin 阳性细胞增殖,但是这些细胞并不表达SDNSF。     

铜离子引起大鼠黑质多巴胺能神经元的退行性变

目的探讨黑质（substantia nigra,SN）内注射不同剂量的CuSO45H2O对大鼠黑质纹状体系统多巴胺能神经元的影响。方法实验用Wistar大鼠,分成对照组和左侧SN内分别注射10nmol、50nmol、200nmol CuSO。组,7天后采用高效液相色谱法（high performance lipid chromotophotography,HPLC）检测纹状体内多巴胺（dopamine,DA）及其代谢产物的含量;酪氨酸羟化酶（tyrosine hydroxylase,TH）免疫组织化学法检测纹状体内TH免疫阳性纤维的改变;半定量RT-PCR法检测黑质内TH,Caspase-3mRNA的表达量：用生化试剂盒分析大鼠中脑内超氧化物岐化酶（superoxide dismutase,SOD）活性的改变。结果在10nmol CuSO4注射组中,DA及其代谢产物的含量与对照组相比没有统计学差别。但是从50nmol组开始,损毁侧纹状体内DA含量随注射CuSO4剂量的增加而逐渐减少,显示出明显的剂量依赖关系（F=34．16,P〈0．01）。注射50nmol CuSO4组大鼠纹状体内TH免疫阳性纤维明显少于对照组和未损毁侧（F=121．9,P〈0．01）。注射50nmol CuSO4组大鼠SN内THmRNA的表达与对照组相比下降（t=3．12,P〈0．01）,但Caspase-3mRNA的表达量与对照组相比却明显增加（t=8．96,P〈0．01）。在注射50nmolCuSO4组中,大鼠损伤侧中脑内SOD的活性与对照组相比下降（t=2．33,P〈0．01）。结论铜离子可以导致大鼠黑质内多巴胺能神经元的损伤,该损伤作用可能是通过破坏抗氧化保护系统和促进细胞凋亡而实现的。     

经颅重复性磁刺激后大鼠纹状体FosB蛋白的表达

观察经颅重复性低频磁刺激（rTMS)对大鼠纹状体FosB蛋白表达的影响。6－OHDA单侧损毁纹状体边缘区,磁刺激器给予大鼠头部1Hz,100mT的重复性刺激,14d后用免疫组织化学ABC法检测纹状体FosB免疫阳性产物。rTMS后能够引起大鼠纹状体区域明显的FosB蛋白表达,这种表达广泛分布于尾壳核及苍白球,尤以腹侧纹状体及尾侧的壳核明显。6－OHDA损毁后予以rTMS,损毁侧Fos蛋白表达未出现减少,且尾壳核的背外侧部表达明显上调。对照组动物仅损毁侧有少量的FosB表达外,纹状体内未见FosB阳性标记。经颅重复性低频磁刺激能够激活纹状体内神经元,推测rTMS可能在增加多巴胺释放的同时,又能够激活多巴胺受体的活性,故在帕金森病等的治疗上有一定的意义。     

神经干细胞生存因子在大鼠脊髓损伤前后的表达变化

目的观察大鼠脊髓损伤后干细胞来源的神经干细胞生存因子（SDNSF）mRNA在大鼠正常和损伤脊髓的农达变化,以及SDNSF的表达与Ⅵ类中间丝蛋白的表达之间的关系。方法按改良的Allen重物打击法制备大鼠脊髓损伤模型,采用RT—PCR、原位杂交方法,观察SDNSF mRNA在大鼠脊髓中的表达位置及在损伤脊髓中的表达变化。应用免疫组化的方法,显示脊髓中nestin的表达。结果RT-PCR检测SDNSF mRNA在正常大鼠脊髓中的表达,损伤后4天SDNSF的mRNA表达上升,损伤8天剑达高峰,此后SDNSF的mRNA表达逐渐减少,到16天恢复到正常水平;脊髓切片原位杂交结果发现SDNSF的mRNA阳性细胞主要分布十脊髓灰质细胞中,可能足神经元细胞,结果表明正常脊髓可表达SDNSF;脊髓损伤后8犬,原位杂交硅示SDNSF阳性细胞明显增多。同时与此切片相邻层面的切片免疫组化证实nestin阳性细胞增殖、变大、向周围发出突起,但这些阳性细胞在分布上与SDNSF无关。结论（1）SDNSF在脊髓中表达于灰质,脊髓损伤后SDNSF的mRNA表达随时间发生变化。（2）随着脊髓损伤的修复,nestin阳性细胞增殖,但是这些细胞并不表达SDNSF。     

重组人促红细胞生成素(rhEPO)对帕金森病大鼠模型小胶质细胞活化的影响

目的探讨重组人促红细胞生成素(recombinant human erythropoietin,rhEPO)对6-羟基多巴胺(6-OHDA)诱导的SD大鼠帕金森病(PD)模型小胶质细胞活化的影响。方法 40只SD大鼠随机分为A组(rhEPO+6-OHDA)、B组(生理盐水+6-OHDA)、C组(6-OHDA)、D组(生理盐水),每组10只。(1)A组:右侧纹状体内立体定向注射重组促红细胞生成素(rhEPO),24h后同侧黒质内立体定向注射6-OHDA;(2)B组:右侧纹状体内立体定向注射与rhEPO等量的生理盐水,24h后同侧黒质内立体定向注射6-OHDA;(3)C组:右侧黒质内立体定向注射6-OHDA;(4)D组:右侧黒质内立体定向注射与6-OHDA等量的生理盐水。4w后采用免疫组化检测黒质内酪氨酸羟化酶(TH)阳性神经元和CD11b阳性细胞数量及CD11b阳性细胞形态变化。结果与D组比较,A组大鼠黒质TH阳性神经元明显减少,CD11b阳性细胞明显增多,大部分小胶质细胞胞体小,突起细长;与B组和C组比较,A组大鼠黒质TH阳性神经元显著增多,CD11b阳性细胞显著减少,仅有少量小胶质细胞胞体大,突起短粗。结论重组人促红细胞生成素(rhEPO)可能通过抑制小胶质细胞活化,减轻6-OHDA对多巴胺(DA)能神经元的毒性损害,对DA能神经元产生神经保护作用。     

卡马西平对匹罗卡品诱导成年癫间疒大鼠海马齿状回神经前体细胞增殖的影响

目的研究卡马西平对成年癫大鼠海马齿状回内源性神经前体细胞增殖的影响。方法采用氯化锂和匹罗卡品联合诱导大鼠癫模型,将癫大鼠随机分为癫对照组和癫卡马西平组,正常大鼠随机分为正常对照组和正常卡马西平组。癫对照组和正常对照组给以蒸馏水灌胃,同时癫卡马西平组和正常卡马西平组给予卡马西平灌胃。于灌胃后第6d腹腔注射5-溴脱氧尿苷嘧啶(BrdU)标记海马齿状回的内源性神经前体细胞的增殖情况;用免疫组化方法观察各组大鼠在注射BrdU后第1d、第7d齿状回BrdU阳性细胞数量的表达。结果①注射BrdU后第1d,癫对照组大鼠海马齿状回BrdU阳性细胞数较正常对照组明显增加(P<0.01),癫卡马西平组大鼠海马齿状回BrdU阳性细胞数较癫对照组减少(P<0.05);②注射BrdU后第7d,癫对照组大鼠海马齿状回BrdU阳性细胞数较正常对照组明显增加(P<0.01),癫卡马西平组大鼠海马齿状回BrdU阳性细胞数较癫对照组明显减少(P<0.05)。结论卡马西平抑制癫大鼠海马齿状回内源性神经前体细胞增殖。     

高压氧预处理对大鼠脊髓损伤后GFAP和巢蛋白表达的影响

目的探讨高压氧预处理对成年大鼠脊髓损伤后不同时期巢蛋白（nestin）和胶质纤维酸性蛋白（GFAP）表达变化的影响。方法成年SD大鼠55只，雌性，体重250～300g。随机分为高压氧预处理组、正常损伤组各25只（n=5），对照组5只。采用改良Allen＇s法制作模型，分别于伤后1d、5d、7d、10d和14d取材，免疫组化染色及图像分析检测组织中GFAP和巢蛋白的表达。结果对照组显示除脊髓中央管周围可见到少量巢蛋白表达外，其它部位几乎不表达；GFAP在脊髓各个部位均有表达；正常脊髓损伤组：1d损伤区域巢蛋白和GFAP表达增加；5d表达显著增加；7d达高峰；10～14d逐渐下调，与对照组差异明显；高压氧预处理组：各时间段均与正常损伤组有明显差异（P〈0．05）。结论高压氧预处理可诱导巢蛋白高表达和星形胶质细胞增生，对中枢神经系统损伤起到保护作用。     

功能性电刺激促进急性脑梗死大鼠脑部内源性神经干细胞增殖的研究

目的 研究功能性电刺激(FES)对急性脑梗死大鼠行为学和内源性神经干细胞(NSC)增殖的影响.探讨FES治疗改善脑梗死后神经功能的机制. 方法 54只成年雄性SD大鼠按随机数字表法分为FES治疗组、安慰刺激组和假手术组(每组各18只).行大脑中动脉阻断(MCAO)制作局灶性脑梗死模型后第3天,FES治疗组开始接受FES治疗(10 min/d,每天1次),安慰刺激组阻断动脉但不予电刺激.在FES治疗后3、7、14d评价大鼠行为学功能(平衡木行走测评、转棒上行走测评、网屏试验),免疫组织化学法观察大鼠海马齿状回和室管膜下区NSCs巢蛋白(nestin)的表达水平.Western blot法检测梗死侧脑组织nestin总蛋白表达量. 结果 FES治疗组网屏试验评分在治疗后14 d时低于安慰刺激组,比较差异有统计学意义(P<0.05).FES治疗组大鼠海马齿状回和室管膜下区nestin阳性细胞数和梗死侧脑组织nestin总蛋白表达量在治疗后7d、14d时均高于安慰刺激组和假手术组,比较差异有统计学意义(P<0.05).结论 FES能促进急性脑梗死大鼠脑部内源性NSCs的增殖并改善大鼠行为学功能,这可能是FES治疗改善脑梗死后神经功能的机制之一.     

Nestin expression in hippocampal astrocytes after injury depends on the age of the hippocampus

Analysis of the expression of nestin in reactive astrocytes facilitates quantification of the extent of activation of astrocytes after injury in the mature CNS. We hypothesize that the capability of astrocytes for re-expressing nestin in response to CNS injury diminishes as a function of age. We quantified astrocytes positive for S-100beta protein, glial fibrillary acidic protein (GFAP) and nestin in the hippocampus of young adult, middle-aged, and aged Fischer 344 rats after an intracerebroventricular kainic acid (KA) administration. In all age groups, KA administration induced degeneration of CA3 pyramidal neurons, which led to a significant deafferentation in the CA1 region. The KA-induced neurodegeneration and deafferentation resulted in an increased population of astrocytes positive for S-100beta and glial fibrillary acidic protein (GFAP) in all age groups. Interestingly, these increases were highly comparable across the three age groups. However, in areas of both neurodegeneration and deafferentation, the overall numerical density of nestin-positive reactive astrocytes varied depending on the age at the time of injury with noticeably decreased numerical density in the injured middle-aged and aged hippocampus. In contrast, nestin-immunoreactive radial glia framework after lesion is not impaired with aging in the ependymal lining of the CA3 region.     

Temporal profile of nestin expression after focal cerebral ischemia in adult rat

Nestin is an intermediate filament protein, transiently and abundantly expressed early in embryogenesis, e.g., in neuroepithelial cells, radial glia, germinal matrix cells and vascular cells. In the adult rat brain, nestin is only present in endothelial and select subventricular cells. We tested the hypothesis that after an experimental stroke, nestin expression is induced in glial cells and neurons. We measured the temporal profile of nestin expression after induction of focal cerebral ischemia in adult rats. Brain from rats (n=24) subjected to 2 h of transient middle cerebral artery occlusion (MCAo) and 3 h, 6 h, 12 h, 1 day, 2 days, 3 days, 7 days and 28 days (n=3, per time point) of reperfusion, and control sham operated (n=3) rats were processed for Western blotting to quantify nestin. Another set of brains from rats (n=28), subjected to 2 h of MCAo and 6 h, 12 h, 2 days, 7 days, 14 days, 21 days, and 28 days (n=4, per time point, except n=8 at 2 days) of reperfusion, and control sham operated (n=3) and normal (n=2) rats were processed by single and double labeled immunohistochemistry for cellular identification of nestin expression. By Western blotting, nestin within ischemic tissue increased slightly as early as 6 h, peaked at 7 days, and expression persisted for at least 4 weeks after 2 h of MCAo. By immunohistochemistry, nestin was expressed in astrocytes in the ischemic core from 6 to 12 h after MCAo. Nestin immunoreactivity was present in large numbers of astrocytes, and in scattered oligodendroglia and monocytes/macrophages in both the inner and outer boundary zones to the ischemic core at 1–7 days after MCAo. Nestin expression in glial cells declined at longer durations of survival, although for least 4 weeks after MCAo the nestin immunoreactivity delineated the boundary zone adjacent to the ischemic core. Nestin expression was present in some neurons localized to the outer boundary zone of the ischemic lesion in the cortex and striatum, and in most ependymal cells in the ventricular and subventricular zone (VZ/SVZ) from day 2 after MCAo and onward. The expression of nestin increased throughout the microvasculature in both the ischemic core and the boundary zone in all ischemic rats after 12 h of reperfusion. After stroke, nestin immunoreactivity in glial, neuronal and ependymal cells is suggestive of a protein expression pattern found in developing brain.     

Cell proliferation and nestin expression in the ependyma of the adult rat spinal cord after injury.

A population of precursor cells is known to exist in the subependyma of the lateral ventricles in adult rodents. However, the source of the precursor cells in the adult mammalian spinal cord has not been identified in vivo, although the adult spinal cord was recently reported to contain neural stem cells in vitro. In this study we found active cell proliferation and nestin expression in the adult ependyma of the central canal after spinal cord injury. The normal ependyma showed limited proliferative activity indicated by a low Ki-67 labeling index (1.5% at T1 level) and no immunoreactivity to nestin, a marker for neural precursor cells. In contrast, the spinal cord injured by clip compression demonstrated a dramatic increase in ependymal proliferation indicated by a high Ki-67 labeling index (maximum of 26% at 3 days [d] after injury) and concomitant strong nestin expression in the ependyma. These responses were downregulated by 7 d after injury. The increased cell proliferation in the ependyma was observed only at sites immediately adjacent to the lesion. After injury, nestin positive, GFAP negative cell populations were found in areas surrounding the ependymal layer, which suggests migration of the ependymal cells. These results indicate the precursor cell qualities of the adult ependyma after injury. Thus, we propose the ependyma of the central canal, which is normally latent but activates locally and temporally in response to spinal cord injury, as the in vivo source for precursor cells in the adult mammalian spinal cord.     

脑缺血后大鼠大脑新皮质的nestin表达与神经节苷脂GM1的关系

目的观察大鼠缺血脑损伤后,外源性单唾液酸四己糖神经节苷脂(GM1)与大脑新皮质巢蛋白(nestin)的表达的关系。方法Wistar成年大鼠随机分配到GM1组、对照组和假手术组;建立大脑中动脉永久梗死性模型,腹腔注射GM1后,利用免疫组织化学染色方法,观察模型大鼠大脑新皮质的巢蛋白表达。结果(1)GM1组表达nestin的细胞数明显比对照组和假手术组多,对照组又明显比假手术组多;(2)对照组表达nestin的细胞数是在干预后7d达最高,干预后10d与3d相比,无差别;GM1组则是干预后7d达高峰,10d后下降,但仍比3d的高。结论GM1能促进缺血脑组织的nestin表达的增加。     

Transplanted human embryonic neural stem cells survive,migrate, differentiate and increase endogenous nestin expression in adult rat cortical peri‐infarction zone

Transplantation of stem cells is a potential therapeutic strategy for stroke damage. The survival, migration, and differentiation of transplanted human embryonic neural stem cells in the acute post‐ischemic environment were characterized and endogenous nestin expression after transplantation was investigated. Human embryonic neural stem cells obtained from the temporal lobe cortex were cultured and labeled with fluorescent 1,1′‐dioctadecy‐6,6′‐di (4‐sulfopheyl)‐3,3,3′,3′‐tetramethylindocarbocyanin (DiI) in vitro. Labeled cells were transplanted into cortical peri‐infarction zones of adult rats 24 h after permanent middle cerebral artery occlusion. Survival, migration, and differentiation of grafted cells were quantified in immunofluorescence‐stained sections from rats sacrificed at 7, 14, and 28 days after transplantation. Endogenous nestin‐positive cells in the cortical peri‐infarction zone were counted at serial time points. The cells transplanted into the cortical peri‐infarction zone displayed the morphology of living cells and became widely located around the ischemic area. Moreover, some of the transplanted cells expressed nestin, GFAP, or NeuN in the peri‐infarction zone. Furthermore, compared with the control group, endogenous nestin‐positive cells in the peri‐infarction zone had increased significantly 7 days after cell transplantation. These results confirm the survival, migration, and differentiation of transplanted cells in the acute post‐ischemic environment and enhanced endogenous nestin expression within a brief time window. These findings indicate that transplantation of neural stem cells into the peri‐infarction zone may be performed as early as 24 h after ischemia.     

室管膜细胞在大鼠脊髓损伤后的反应性增生

目的旨在探讨成年大鼠脊髓损伤后室管膜细胞的增殖反应,为进一步促进脊髓损伤后自身修复提供理论依据。方法应用动脉瘤夹压迫建立大鼠脊髓压迫损伤模型,通过组织病理学及免疫组织化学方法检测不同时段室管膜细胞的反应性增生和神经外胚层多潜能细胞特异性抗原巢蛋白(nestin)的表达。结果常规病理学检查显示损伤模型类似于临床常见的脊髓横贯伤,损伤后24h可以观察到室管膜细胞nestin表达明显升高,增殖细胞核抗原(PCNA)呈阳性;1周后见室管膜细胞显著增生;nestin的表达随时间进展呈向下调节。结论静止的室管膜细胞有潜在的增殖能力,在脊髓损伤后表现出明显的分裂增生,可能在结构和功能重塑过程中起作用。     

雌激素致癎作用部位的研究

目的了解雌激素在癫癎大鼠中枢神经系统的作用部位.方法利用海人酸致癎和6-氟二乙酯致癎的两种不同机制的癫癎模型(单纯致癎组),应用免疫组化法检测单纯致癎及给予雌激素后再致癎大鼠海马、大脑皮质、纹状体的FOS表达.结果两种模型单纯致癎组海马、皮质、纹状体FOS表达较正常组显著增高(均P＜0.01).给予雌二醇(E2)后再致癎,海人酸模型中海马、皮质FOS表达较单纯致癎组增加(P＜0.01,P＜0.05);而6-氟二乙酯模型中无变化.结论在两种不同致癎机制的癫癎模型中,雌二醇对鼠脑FOS表达的影响不同.     

糖皮质激素对大鼠内源性神经前体细胞增殖的影响

目的探讨大剂量糖皮质激素(GCs)对成年大鼠内源性神经前体细胞增殖的影响.方法将25只大鼠随机分为对照组和地塞米松(DEX)作用1、3、7、14 d组,应用免疫组化方法检测神经前体细胞标记物巢蛋白(nestin)的表达,并通过5-溴脱氧尿苷(BrdU)观察神经前体细胞的增殖.结果正常大鼠海马齿状回(DG)和室下区(SVZ)存在神经前体细胞,并且其中一些细胞处于分裂增殖状态.应用大剂量GCs作用3、7、14 d组与对照组相比DG的nestin和BrdU阳性细胞数明显减少,SVZ的nestin和BrdU阳性细胞数在DEX作用7、14 d组与对照组相比明显减少,并且DG与SVZ二者阳性细胞数随着作用时间的延长而减低更为明显.结论大剂量GCs持续作用可抑制大鼠脑内的内源性神经前体细胞的增殖,DG区的神经前体细胞对GCs的反应较SVZ更为敏感.