PROLIFERATION AND MIGRATION OF EPENDYMAL CELLS IN THE BRAIN OF ADULT RATS AFTER PERMANENT FOCAL CEREBRAL ISCHEMIA

Objective Ependymal cells are thought to be the primary source of neural stem cells in the adult central nervous system. The purpose of this study is to examine spatial and temporal profiles of ependymal cell proliferation and migration after focal cerebral ischemia. Methods Eighty male Sprague Dawley rats underwent permanent middle cerebral artery occlusion after injection of 10/μL of 0.2% Dil into the lateral ventricle. Rats were sacrificed and brain sections were acquired for pathological evaluation and laser confocal imaging at day 1,3,7,11,14,21 and 28 after ischemia. Results The density of Dil-labeled cells in the ischemic ipsilateral subventricular zone was significantly higher than that in the control group and these labeled cells dispersed in the ischemic ipsilateral subventricular zone and/or were located in ependyma from day 1 to 11. In the ischemic ipsilateral cortex, some Diilabeled cells occurred in peri-infarction and infarction of parietal region at day14 and peaked at day 21 when some Dil-labeled cell nodules were found in this region. During postischemic day 14--28, a significant decrease in labeled celldensity in the ischemic ipsilateral subventricular zone was coincident with a significant increase in labeled cells density in the cortex (peri-infarction and infarction). Conclusion The results indicate that ependymal cells proliferate and migrate after focal cerebral ischemia in the adult rat brain.     

β-淀粉样蛋白增加基底前脑神经元对谷氨酸的易感性

目的探讨β-淀粉样蛋白25-35(Aβ25-35)与谷氨酸(Glu)联合应用,对原代培养的大鼠基底前脑神经元的作用。方法原代培养大鼠基底前脑神经元,应用形态学、MTT法结合ChAT免疫组织化学染色,分别观察Aβ25-35与Glu联合应用,对原代培养的基底前脑神经元存活率、形态学及ChAT免疫反应阳性神经元的影响。结果将100 nmol/L、1μmol/L Aβ分别和20μmol/L Glu联合用于培养的基底前脑神经元,在倒置显微镜下观察,细胞表面粗糙,立体感减弱,胞浆中出现深色颗粒,细胞肿胀或收缩;尼氏染色显示尼氏体减少;MTT检测显示神经元存活率明显下降,100nmol/L Aβ+20μmol/L Glu组与100 nmol/L Aβ组间,1μmol/L Aβ+20μmol/L Glu组与1μmol/L Aβ组间比较均具有统计学差异(P<0.05);ChAT免疫阳性神经元的灰度和截面积均减小。结论Aβ25-35可增加神经元对Glu神经毒性作用的敏感性,表明Glu在阿尔茨海默病发病中起着非常关键的作用。     

EFFECTS OF DIPSACUS ASPER AND VITAMIN E ON THE SS NEURONS IN THE HIPPOCAMPAL FORMATION OF RAT MODELS OF ALZHEIMER‘S DISEASE

Ａｌｚｈｅｉｍｅｒ’ｓｄｉｓｅａｓｅ (ＡＤ)ｉｓｔｈｅｍｏｓｔｃｏｍｍｏｎｄｅｍｅｎｔｉａｉｎｔｈｅｓｅｎｉｏｒ ,ａｎｄｔｈｅｒｅｉｓｎｏｃｕｒｅｏｒｅｆｆｅｃ ｔｉｖｅｔｒｅａｔｍｅｎｔ .ＡｌｔｈｏｕｇｈｔｈｅｅｔｉｏｌｏｇｙｏｆＡｌｚｈｅｉ ｍｅｒ’ｓｄｉｓｅａｓｅｉｓｎｏｔｆｕｌｌｙｕｎｄｅｒｓｔｏｏｄ ,ａｃｃｕｍｕｌａｔｉｎｇｅｖｉｄｅｎｃｅｄｅｍｏｎｓｔｒａｔｅｓｔｈａｔｂｏｔｈｔｈｅｃｏｎｃｅｎｔｒａｔｉｏｎｏｆｔｈｅｓｏｍａｔｏｓｔａｔｉｎ (ＳＳ)ａｎｄｔｈｅＳＳｎｅｕｒｏｎｓｉｎｔｈ…     

血管活性肠肽对暂时性脑缺血大鼠梗死体积的影响

目的通过活体实验研究血管活性肠肽(VIP)对脑缺血损伤的神经保护作用。方法大鼠侧脑室内注射VIP后,采用大脑中动脉线栓(MCAO)法诱导建立暂时性局部脑缺血模型。通过神经学的评价对MCAO大鼠进行判定和筛选;TTC染色测定大鼠脑梗死体积;双抗夹心ELISA检测血清S100β的含量。结果MCAO后2 h大鼠呈现不同程度的神经功能损伤症状。评定为1-2级的仅有2例出现明显脑梗死区,3级的为全部。VIP注射后大鼠脑梗死体积明显缩小,较对照组减少约25%(P<0.05);血清S100β浓度也明显降低(P<0.05)。结论以神经学评分3级作为MCAO模型成功的判定标准是较为可靠的。VIP脑内注射可明显减小脑缺血后梗死体积,具有神经保护作用。VIP可以降低S100β的含量,这可能涉及到VIP的另一神经保护机制。     

β-淀粉样蛋白诱导大鼠海马S100β表达的作用及机制

目的　探讨 β 淀粉样蛋白 (Aβ)对S10 0 β表达的影响及作用机制。 方法　采用Aβ2 5-3 5和IL 1ra ,选择大鼠海马CA1区进行定位注射 ,通过行为学测试、刚果红染色和免疫组化技术结合图像分析的方法 ,对不同时间大鼠的学习记忆、淀粉样沉积、GFAP和海马CA1区S10 0 β表达的变化进行观测。 结果　Aβ2 5-3 5注射后 ,大鼠的学习记忆能力明显下降 ;海马CA1区出现Aβ沉积 ,并有大量GFAP阳性胶质细胞包绕 ;实验组S10 0 β阳性细胞数目在 3、7、2 1d较对照组均有明显增多 ,细胞平均面积只在 2 1d才有明显增大。脑内注射IL 1ra后 3、7d,S10 0 β阳性细胞数目明显低于同组的Aβ大鼠 ,而高于对照组。结论　Aβ2 5-3 5脑内注射可建立具有类似阿尔茨海默病的局部病理改变和学习记忆损害的AD动物模型 ;Aβ2 5-3 5可上调大鼠海马CA1区S10 0 β的表达 ,实验早期以S10 0 β阳性细胞的数目增加为主 ,后期表现为细胞体积的增大 ;IL 1ra脑内注射可明显降低Aβ2 5-3 5上调S10 0 β表达的作用 ,其机制是阻断由Aβ2 5-3 5激活的小胶质细胞释放的IL 1对星形胶质细胞的活化作用。     

THE PROTECTIVE EFFECTS OF THE TOTAL SAPONIN OF DIPSACUS ASPEROIDES ON THE APOPTOSIS OF HIPPOCAMPAL NEURONS INDUCED BY β-AMYLOID PROTEIN

Objective To investigate the effects of the total saponin of Dipsacus asperoides (tSDA) and ginsenoside Rb1 (GRb1) on the apoptosis of primary cultured hippocampal neurons induced by β-amyloid protein (Aβ). Methods Primary cultured hippocampal neurons, the cultures were pretreated with tSDA and GRb1 on 10d for 24 hours respectively. Then the cultures were treated with 35μmol·L-1 Aβ25-35 for 24 hours, observed the changing of survival rate of neurons and the apoptosis of neurons with biochemical analysis combining immunofluorescent cytochemical double-staining technique. Results Hippocampal neurons were treated with 35μmol*L-1 Aβ for 24 hours, and survival rate of neurons downed to 52.6%. When neurons were pretreated by tSDA and GRb1, survival rate of neurons increased 11% to 15%. The findings of immunofluorescent cytochemical double-staining indicated that apoptotic neurons were obviously more than that of the blank group, reaching 43.9%.When neurons were pretreated by tSDA and GRb1, apoptotic neurons were downed to 16.6%, 10.8% respectively. Conclusion tSDA had the same effects as GRb1, protecting the neurons, antagonizing neurotoxicity of Aβ, increasing survival rate of neurons, and reducing apoptotic neurons induced by Aβ.     

下丘脑外侧区微量注射胃动素对大鼠十二指肠消化间期复合肌电活动的影响

目的探讨下丘脑外侧区(LHA)微量注射胃动素对十二指肠消化间期复合肌电活动(IMC)的影响及其机制。方法采用中枢立体定位LHA微量注射的方法,观察静脉给予阿托品(50μg/kg)、酚妥拉明(200μg/kg)、普萘洛尔(100μg/kg)及抗胃动素血清(1∶50)和膈下迷走神经切断后,LHA微量注入胃动素(0.37 nmol)对十二指肠IMC的影响。结果LHA微量注入胃动素可以使十二指肠IMC周期明显变短,峰电振幅增加,峰电频率增快,但对峰电时相无明显影响;膈下迷走神经切断可完全阻断LHA微量注射胃动素对十二指肠IMC的影响;阿托品、酚妥拉明、普萘洛尔不能阻断LHA微量注射胃动素对十二指肠IMC的影响;抗胃动素血清只能部分阻断LHA微量注射胃动素对十二指肠IMC的影响。结论LHA外源性胃动素可改变十二指肠IMC的特征并在其调节中发挥着重要作用。     

川续断总皂甙对β-淀粉样蛋白诱导海马神经元凋亡的保护作用

目的研究川续断总皂甙(tSDA)和人参皂甙Rb1(GRb1)对β淀粉样蛋白(Aβ)介导引起的原代培养海马神经细胞凋亡的影响,旨在阐明tSDA抗Alzheimer病(AD)机理奠定基础.方法原代培养海马神经细胞,于培养第10天用tSDA和GRb1分别预先处理培养细胞24 h,然后再用35 μmol·L-1Aβ处理培养细胞24 h,采用生化分析和免疫荧光细胞化学双标技术观察神经细胞生存率和凋亡变化.结果用35 μmol·L-1Aβ 25～35处理海马神经细胞24 h后,神经细胞的存活率降至52.6%;当预先加入tSDA和GRb1后,Aβ毒性减小,神经细胞存活率增加了11%～15%.免疫荧光细胞化学双标检测表明凋亡细胞明显高于空白对照组达43.9%;当预先加入tSDA与GRb1,凋亡神经细胞分别降至16.6%、10.8%.结论 tSDA与GRb1有相类似功效,具有神经保护作用,对抗Aβ神经毒作用,提高细胞生存率,减少由Aβ诱导的神经细胞凋亡.     

THE PROTECTIVE EFFECTS OF THE TOTAL SAPONIN OF DIPSACUSASPEROIDES ON THE APOPTOSIS OF HIPPOCAMPAL NEURONSINDUCED BY β-AMYLOID PROTEIN

Alzheimer sdisease(AD)isaneurodegenerativedisease ,whosehallmarksof pathologyaresenileplaques,βamyloidprotein (Aβ)depositionwith inbrain ,neurofibrillarytanglesformationandalotofneuronalloss .Thefactorsthatleadtoneuronallossareofcomplexityandmultiplicity ,includingthetoxicityofAβ,intracellularfreecalciumcon centrationhomeostasisimbalance ,damageofoxidefreeradicals ,andinitiationofmechanismofapop tosis,etal.[1- 3] .Thedetailedmechanismhasnotreachedadefiniteconclusion .Thepreventionandtreat…     

EFFECT OF THE TOTAL SAPONIN OF DIPSACUS ASPER ON INTRACELLULAR FREE CALCIUM CONCENTRATION IN THE CELLULAR MODEL OF ALZHEIMER‘S DISEASE-SCANNING CONFOCAL MICROSCOPY

ＡｌｔｈｏｕｇｈｔｈｅＡｌｚｈｅｉｍｅｒ’ｓｄｉｓｅａｓｅ(ＡＤ)ｗａｓｄｉｓ ｃｏｖｅｒｅｄｂｙＡｌｏｉｓＡｌｚｈｅｉｍｅｒ ,ａＧｅｒｍａｎｎｅｕｒｏｐａｔｈｏｌｏ ｇｉｓｔ,ｉｎｅａｒｌｙ 2 0ｃｅｎｔｕｒｙ ,ｉｔｄｉｄｎｏｔｇａｉｎｍｕｃｈｐｕｂｌｉｃａｔｔｅｎｔｉｏｎｕｎｔｉｌｔｈｅｌａｓｔｔｗｏｄｅｃａｄｅｓ .Ａｓｔｈｅｌｉｆｅｓｐａｎｏｆｈｕｍａｎｂｅｉｎｇｓｐｒｏｌｏｎｇｓ ,ｔｈｅｎｕｍｂｅｒｏｆｐｅｒｓｏｎｓｗｉｔｈＡＤｈａｓａｌｓｏｉｎｃｒｅａｓｅｄ .Ｂｅｓｉｄｅｓｃａｎｃｅｒａｎｄ…