芍药苷对幼鼠癫痫持续状态后海马神经元的保护作用

目的 观察芍药苷对幼鼠癫痫持续状态(SE)后海马神经元的保护作用,探究其作用机制.方法 3周龄SPF级Wistar大鼠72只,随机分为对照组、模型组、芍药苷组(50 mg/kg,i.p.),各组根据干预时间不同分别分为1、3、7 d三个亚组,每个亚组8只.除对照组外,其余各组幼鼠腹腔注射氯化锂-匹鲁卡品诱发SE,观察造...     

丹参酮对原代大鼠海马神经元细胞缺氧缺糖损伤的保护作用

目的观察缺氧缺糖对大鼠海马神经元细胞的影响及丹参酮的保护作用。方法取体外培养12天的海马神经元细胞随机分为正常对照组、缺氧缺糖组、丹参酮20μmol／L组、丹参酮40μmol／L组、丹参酮80μmol／L组（后3组缺氧缺糖前24h,加入丹参酮预处理）。缺氧缺糖组、各浓度丹参酮组在缺氧缺糖环境中培养2、4、24及36h后,收集其各个时间点的培养液,测定培养液中乳酸脱氢酶（LDH）含量。结果缺氧缺糖后,缺氧缺糖组各个时间点LDH渗出量明显高于正常对照组,经丹参酮预处理的神经元损伤有不同程度的减轻,各个时间点LDH渗出量明显低于对应的缺氧缺糖组。结论缺氧缺糖可引起海马神经元损伤,丹参酮对海马神经元细胞损伤具有保护作用。     

人参皂苷对体外培养低氧海马神经元的保护作用

目的 观察人参皂苷（Rg2）对大鼠低氧海马神经元的保护作用及其机制。方法 取新生Wistar大鼠海马神经元体外培养14d,随机分为对照组、5μmol/L尼莫地平组（尼莫地平组）、Rg2 0．025mmol/L组（Rg2 1组）、Rg2 0．050mmol/L组（Rg2 2组）。将相应药物加入到培养液中孵育4h后,连续充以体积分数0．95N2＋体积分数0．05CO2混合气体,建立急性低氧细胞模型。台盼蓝染色计数存活细胞,吉姆萨染色观察细胞形态,荧光分光光度计法测细胞内Ca^2＋浓度。结果 尼莫地平组、Rg2两个剂量组的细胞死亡率均明显低于对照组,以Rg2 2组最低,差异均有显著性（X^2=3．37,P〈0．05）。海马神经元细胞内Ca^2＋浓度在尼莫地平组、Rg2两个剂量组均明显低于对照组,以Rg2 2组最低,差异均有显著性（F=466．58,q=6．76～48．82,P〈0．01）。结论 Rg2可显著降低体外培养大鼠低氧海马神经元的细胞死亡率,其机制可能是通过减少Ca^2＋内流而发挥作用。     

芍药甙对大鼠空肠平滑肌细胞静息膜电位的作用研究

【目的】探讨芍药甙对大鼠空肠平滑肌细胞静息膜电位的调控作用。【方法】酶解法分离大鼠空肠环行平滑肌细胞,全细胞膜片钳方法测定膜电位。静息状态下,平滑肌细胞的膜电位为(-59.3±3.4)mV;加入芍药甙孵育后,膜电位降低至(-65.6±3.0)mV(P=0.007)。【结论】芍药甙可以通过开放Kv通道,使膜超极化,限制Ca2+内流,实现了对平滑肌细胞的舒张作用。     

尼莫地平对海马神经元保护作用的实验研究

目的:探讨尼莫地平对海藻酸(KA)处理海马神经元的保护作用。方法:在体外培养7d的海马神经元中加入不同浓度的尼莫地平(50、100、200μmol/L),30min后分别加入两种浓度的KA(50、100μmol/L),培养24h后,用MTT细胞活性测定法和免疫细胞化学染色评定尼莫地平对KA损伤海马神经元的保护作用。结果:50、100μmol/L的KA均能使海马神经元活性明显下降(P<0.05);50μmol/L的KA所致的神经元活性下降可被50、100、200μmol/L的尼莫地平阻断(P<0.05),仅200μmol/L的尼莫地平可阻断由100μmol/L的KA所致的神经元活性的下降(P<0.05)。免疫细胞化学染色所示的海马神经元形态学变化同MTT检测结果基本一致。结论:尼莫地平对KA所致的海马神经元损伤具有剂量依赖性保护作用。     

天麻素对酸中毒诱导的大鼠海马神经元损伤的保护作用

脑组织pH值下降、酸中毒是很多疾病如脑外伤、癫痫、脑中风的病理现象,也是导致神经元损伤的主要致病因素[1,2]。天麻素是天麻的主要有效成分,具有抗谷氨酸兴奋性毒性和氧自由基损伤作用[3,4],并且广泛用于神经系统疾病的治疗。近年来,对天麻素的药理作用展开了广泛的研究,如抗     

脑心通对大鼠脑缺血海马CA1区神经元损伤的保护作用

OBJECTIVE: To examine the neuroprotective effects of Naoxintong and Zhongfenghuichunwan on neuronal injury in CA1 region of rat hippocampus following transient forebrain ischemia. METHODS: Transient rat forebrain ischemia for 15 min was induced by modified four-vessel occlusion method. The density of survived pyramidal cells (neurons per 1 mm linear length) in CA1 region of the hippocampus was measured under light microscope. RESULTS: In Naoxintong or nimodipine-treated rats, the density of survived pyramidal cells in CA1 region was significantly greater than that of saline group (P<0.05, P<0.001, respectively), but oral administration of Zhongfenghuichunwan had no obvious effect on ischemia-induced neuronal damage in CA1 region. CONCLUSION: Naoxintong can protect CA1 neurons against ischemic insult in rats.     

Protective effect of cardiomyopeptidin on cultured rat hippocampal neurons injured by anoxia reoxygenation

Cardiomyopeptidin (CMP), a small molecular polypeptide, is a new drug extracted from pig myocardium. Recently, evidence of its protective effect on myocardium injured by ischemia or anoxiah as appeared. Neurons are also vulnerable to ischemia/anoxia. The aim of this study was to evaluate the neuroprotection of CMP in an anoxic model, which was the cultured hippocampal neurons in vitro, and to determine the relationship between CMP and expression of Bcl-2.     

氧化苦参碱对大鼠海马神经元细胞钠通道的影响

目的 研究氧化苦参碱(oxymatrine,OMT)对培养的新生大鼠海马神经元细胞膜钠电流作用,探讨OMT在离子通道水平的作用机制.方法 采用原代培养新生大鼠海马神经元细胞,应用全细胞膜片钳技术,观察不同浓度OMT对培养8～12天的大鼠海马神经元细胞膜钠通道的作用.结果 OMT对海马神经元细胞膜钠电流有明显的抑制作用(n=20,P＜0.05),且这种作用具有浓度依赖性,OMT对钠电流作用的半数抑制浓度为(46.1±1.3)μmol/L.在30μmol/L时,OMT可使钠电流Ⅰ～Ⅴ曲线显著上移,并且改变钠电流的翻转电位,但不影响激活电位和峰电位.通道动力学显示OMT可以促进钠电流复活曲线向右移动,减慢通道由失活状态恢复到激活状态的过程,但对激活曲线和失活曲线则没有明显的作用.结论 OMT呈浓度依赖性和电压依赖性抑制大鼠海马神经元细胞膜钠电流,并且抑制钠通道的复活过程.     

三氧化二砷对海马神经元细胞内钙离子浓度的影响

目的 研究三氧化二砷(As2O3)对海马神经元细胞内钙离子([Ca2 ]i)浓度的影响与其神经毒性的可能机制.方法 用激光共聚焦显微镜结合Fluo-3-AM观察As2O3对大鼠原代培养的海马神经元[Ca2 ]i的影响.结果 有钙液中10 μmol/L、100 μmol/L As2O3升高海马神经元[Ca2 ]i与对照组相比[Ca2 ]i分别提高了0.24±0.09和0.41±0.08.20 μmol/L的维拉帕米不能阻断10 μmol/L As2O3升高[Ca2 ]i作用.无钙液中10 μmol/L、100 μmol/Ls2O3升高海马神经元[Ca2 ]i与对照组相比[Ca2 ]i分别提高了0.12±0.06和0.30±0.07.100 μmol/L 2-APB阻断了10 μmol/L As2O3升高[Ca2 ]i作用.结论 As2O3可以升高海马神经元[Ca2 ]i,IP3信号转导途径可能参与As2O3升高海马神经元[Ca2 ]i.     

NMDA受体在培养神经元突触内和突触外发育中的变化

目的 观察培养大鼠海马神经元NMDA受体在突触内和突触外发育中的变化.方法 采用膜片钳的全细胞模式和外面向外模式分别记录突触内和突触外NMDA受体通道电流.结果 培养2周海马神经元突触内NMDA受体通道介导的微小兴奋性突触后电流(mEPSCNMDA)幅度比培养1周神经元小,对NMDA受体亚单位NR2B的特异拮抗剂ifnprodil的敏感性远低于培养1周神经元;培养2周神经元突触外NMDA受体的单通道电流幅度和开放概率比培养1周神经元增大,但两者的电导和翻转电位无显著差异.ifenprodil降低培养1周和2周神经元突触外NNDA受体单通道电流的电导和开放概率,且对培养2周神经元开放概率的抑制作用更显著.结论 NMDA受体通道电流在培养海马神经元突触内和突触外有发育变化,提示NMDA受体NR2亚单位在培养1周的神经元突触内和突触外均主要为NR2B亚单位;而神经元培养到2周时,突触内NR2B亚单位逐渐被NR2A亚单位取代,突触外仍主要为NR2B亚单位.     

Rapid effect of stress concentration corticosterone on glutamate receptor and its subtype NMDA receptor activity in cultured hippocampal neurons

Objective: To study the rapid effect of glucocorticoids (GCs) on NMDA receptor activity in hippocampal neurons in stress and to elucidate its underlying probable membrane mechanisms. Methods: Whole-cell patch-clamp recording was used to assess the effect of stress concentration corticosterone (B) on the responses of cultured hippocampal neurons to glutamate and NMDA (N-methy-D-asparatic acid). To make clear the target of B, intracellular dialysis of B(10μmol/L)through patch pipette and extracellular application of bovine serum albumin-conjugated corticosterone (B-BSA, 10μmol/L)were carried out to observe their influence on peak amplitude of NMDA-evoked current. Results: B had a rapid, reversible and inhibitory effect on peak amplitude of GLU-or NMDA-evoked current in cultured hippoeampal neurons. Furthermore, B-BSA had the inhibitory effect on INMDA as that of B, but intraeeUularly dialyzed B had no significant effect on INMDA. Conclusion: These results suggest that under the condition of stress, GCs may rapidly, negatively regulate excitatory synaptic receptors-glutamate receptors (GluRs), especially NMDA receptor (NMDAR) in central nervous system, which is mediated by rapid membrane mechanisms, but not by classical, genomic mechanisms.     

黄芪对原代培养海马神经元的作用及其对抗缺血缺氧损伤的机制

目的：研究黄芪注射液对体外培养的海马神经元的影响;探索缺血缺氧对海马神经元的损伤作用及黄芪对抗缺血缺氧损伤的机制．方法：在体外培养新生大鼠大脑海马神经元,实验组加入不同浓度的黄芪,观察黄芪对培养的海马神经元的量效作用,应用MTT法检测神经元存活率作为反应指标;通过运用无糖DMEM培养基、去除培养液中的血清外加N2取代O2造成神经元缺血缺氧细胞损伤模型,加入最适剂量的黄芪,观察黄芪对上述损伤的作用;通过MTT法测定存活细胞数,乳酸脱氢酶（LDH）漏出量的检测,BDNF,NGF及NT-3免疫细胞化学染色等检测指标来反映缺血缺氧对神经元的损伤作用,同时观察黄芪对抗损伤的机制．结果：适宜剂量黄芪可提高体外培养的海马神经元的存活率,其最适宜浓度为300g／L;大剂量的黄芪（超过800g／L）可对体外培养的海马神经元造成毒副作用,使得神经元存活率下降;缺血缺氧可导致海马神经元胞膜发生脂质过氧化损伤,导致LDH外漏增加;缺血缺氧损伤可导致大量神经元死亡,这其中包括坏死和凋亡,在BDNF,NGF及NT-3三种神经营养因子中,BDNF受缺血缺氧的影响最大,表现为其表达明显下调．黄芪可对抗缺血缺氧损伤而保护神经元,它可减轻神经元脂质过氧化,并抑制缺血缺氧引发的BDNF表达下调．结论：适宜剂量的黄芪可提高体外培养的海马神经元的存活率,并且可以对抗缺血缺氧损伤而保护神经元．     

The effect of coriaria lactone on NMDA receptor mediated currents in rat hippocampal CA1 neurons

Epileptogenesis of (CL) has been verified bymany studies. We can establish an ideal animalmodel of epilepsy on the basis of these studiesll' ZJ.Homeostasis of cytoplasmic free Ca2 is the basisfor neuron to perform its normal functions. Theabnormal elevation of cytoplasmic free Ca2 is thekey step in the triggering of a series of pathologicalchanges"'. Our past findings showed that CLcould elevate LCa' j, of hippocampal neurons[4].But there was no report about the way thoughwhich CL ele…     

脑益康含药血清对D-半乳糖诱导海马神经细胞损伤的保护作用

目的:研究脑益康对D-半乳糖(D-gal)诱导新生大鼠海马神经细胞损伤的保护作用。方法:运用血清药理学方法采集脑益康含药血清,D-gal复制海马神经细胞损伤模型,通过倒置显微镜观察海马神经细胞形态,MTT法测定海马神经细胞的活性。结果:脑益康保护组海马神经细胞数显著高于D-gal损伤组,受损的细胞数较少。结论:脑益康对D-gal损伤的海马神经细胞具有保护作用。     

锌对新生大鼠海马神经元bcl-2 mRNA表达的影响

目的：观察微量元素锌对新生大鼠海马神经元细胞凋亡抑制基因ｂｃｌ－２ｍＲＮＡ表达的影响。探讨锌影响中枢神经系统发育的分子机制。方法;采用无血清培养Ｗｉｓｔａｒ新生儿大鼠海马神经元细胞,分别在无血清培养液中加入不同浓度的ＺｎＳＯ４溶液培养７ｄ,采用图像分析技术分析其生长分化情况;收集海马神经元细胞,利用Ｎｏｒｔｈｅｒｎ杂交技术检测海马神经元ｂｃｌ－２ｍＲＮＡ表达情况。结果：锌可通过提高ｂｃｌ－２ｍＲＮ     

Experimental Study of Effect of Corticosterone on Primary Cultured Hippocampal Neurons and Their Ca^2＋／CaMK Ⅱ Expression

Summary: To explore the effect of different concentrations of corticosterone (CORT) on primary cultured hippocampal neurons and their Ca^2 /CaMK Ⅱ expression and possible mechanism, the changes of hippocampal neurons were observed in terms of morphology, activity of cells, cell death.concentrations of cytosolic free calcium, and the expression of CaMK Ⅱ by using MTT assay, flow cytometry, fluorescent labeling of Fura-2/AM and Western hlotting after 10^-7. 10^-8 and 10^-5 mol/L of CORT was added to culture medium. The evident effect of 10^-6 and 10^-5 mol/L of CORT on the morphology of hippocampal neuron was found. Compared with control neurons, the activity of the cells was markedly decreased and [Ca^2 ], increased in the neurons treated with 10^-6 and 10^-7mol/L of CORT. but no change was observed in the neuron treated with 10^-7 mol/L of CORT.The death was either by way of apoptosisor necrosis in the cells treated with 10^-4 and 10^-5mol/L of CORT respectively. The correlation analysis showed that a reverse correlation existed between [Ca^2 ];and the expression of CaMKⅡ. Either apoptosis or necrosis occurs in the hippocampal neurons treated with CORT. The increased hippocampal [Ca^2 ], is both the result of CORT impairing the hippocampal neurons and the cause of the apoptosis of hippocampal neurons and the decreased CaMKⅡ expression.