新型tacrine双联体对培养大鼠海马神经元NMDA受体作用位点的研究

目的：研究新型tacrine双联体bis（7）-tacrine对NMDA受体的作用位点.方法：大鼠海马神经元原代培养,全细胞膜片钳记录培养大鼠海马神经元上NMDA激活电流变化.结果：细胞外液pH值从8.1改变到6.7,在细胞外液中加入二硫苏糖醇（2 mmol/L）、精胺（10 mol/L）、镁离子（50～500 mol...     

运动训练大鼠长期停训后海马一氧化氮合成酶的表达变化

摘要：成酶((Nosynthetase,NOS)表达的影响。方法参照Bedford跑台训练方案．建立雄性sD大鼠有氧训练与疲劳训 练动物模型,停训28周。观察大鼠海马神经元NOS的表达变化。结果停训28周后,疲劳训练抑制了停训大鼠 海马NOS的表达。有氧训练促进了停训大鼠海马NOS的表达。结论早年长期有氧训练对改善大鼠海马组织细 胞机能．延缓其衰老,提高学习与记忆能力等方面有积极意义;而长期疲劳训练可能会对其包括学习与记忆能力等 方面的机能状态产生不利影响。     

大鼠脑组织腺苷含量的HPLC分析

用高效液相色谱（ＨＰＬＣ）配紫外检测器，分离测定大鼠脑组织中腺苷含量。经实验确定以甲醇（１０％～６２％）、磷酸缓冲液（９０％～３８％）为流动相梯度洗脱，样品液中腺苷含量在２ｍｇ／Ｌ～１０ｍｇ／Ｌ范围内线性关系良好。加入标准样品的平均回收率为（９６６±２０）％。对６ｍｇ／Ｌ样品１０次重复测定结果的标准偏差为０１４，变异系数为３１％。对大鼠脑组织样品测定结果发现：与３～６月龄成龄鼠比较，１８～２０月龄老龄大鼠大脑皮层、海马、纹状体中腺苷含量分别增加了６６７％、３７２％和２７３％，不同脑区腺苷含量也有明显差异。结果提示不同脑区腺苷含量的随龄增加可作为研究衰老的一项指标；而中枢神经系统中随龄增长腺苷的堆积使Ａｃｈ释放受到抑制可能是出现记忆衰退等常见老年性功能障碍的一个重要原因     

性激素诱导大鼠前列腺增生的免疫组织化学研究

Ｗｉｓｔａｒ雄性大鼠６５只分为正常对照组和实验组．后者均做双侧睾丸摘除术，术后３周根据不同的处理方法分为单纯阉割组、雄激素（Ｔ）处理组和不同比例雌雄激素处理组．以免疫组化ＡＢＣ法观察大鼠前列腺腹叶（ＲＶＰ）内雄激素受体（ＡＲ）和雌激素受体（ＥＲ）含量的变化。结果表明ＲＶＰ内ＥＲ变化不明显，ＡＲ含量在各实验组不同：单纯阉割组动物ＡＲ逐渐减少，雌激素（Ｅ２）与Ｔ同时处理较单用Ｔ处理ＡＲ增加更为显著，Ｅ２增加ＲＶＰ内ＡＲ含量的这种作用须在大鼠体内Ｔ大于一定含量时方能实现。提示Ｅ２可通过增加ＲＶＰ内ＡＲ的含量协同Ｔ对ＲＶＰ正常及异常生长的调节作用，本文对这种效应进行了讨论。     

Impaired auditory sensorimotor gating： An animal model of schizophrenia

Establishment of animal models of schizophrenia is critical for both understanding the mechanisms underlying this severe mental disease and developing new antipsychotics. This paper starts from the theoretical root of sensory gating, the 損rotection-of-processing? theory, then thoroughly describes the representative studies over the past decade on the mechanism underlying prepulse inhibition and on those underlying modulation of prepulse inhibition, which is the normal startle suppression caused by the weak stimulus preceding the intense startling stimulus. The main methods for inducing prepulse inhibition deficits in experimental animals include: ⅰ) modulations of neuro- transmission that are closely associated with schizophrenia; ⅱ) focal lesions or pharmacological manipulations of brain structures in the cortico-striato-pallido-pontine circuit; and ⅲ) maternal deprivation or social isolation. Six essential topics for studies in modeling schizophrenia are suggested at the last part of this review.     

马桑内酯致痫大鼠海马IL-2免疫反应性的变化

目的:探求细胞因子中的白细胞介素2(Interleukin-2,IL-2)与癫痫发病之间的关系。方法:将Wistar大鼠分成三组,第一组侧脑室注入马桑内酯(Coriari Lactone,CL)2μL,第二组注入等量的生理盐水,第三组不做任何处理。然后运用免疫组织化学方法,对大鼠海马IL-2的免疫反应性进行分析;同时对实验中大鼠的行为及脑电图(eletroencepalograph,EEG)进行观察和记录。结果:第一组大鼠侧脑室注射CL过程中即诱发癫痫,且测到痫性脑电图,第二组、第三组无癫痫症状且未记录到痫性脑电图;第一组大鼠海马IL-2免疫反应性较第二组及第三组显著增强(P<0.01),表现在其海马CA_1、CA_2、CA_3区细胞数目增多,突起及其分支增多,着色明显加深;而第二、三组之间无明显差别(P>0.05)。结论:IL-2参与癫痫的发病过程,二者之间存在着一定的联系。     

中枢兴奋性传递的突触后电位小波熵分析研究

采用细胞内记录方法提取了离体大鼠海马脑片CA1区锥体神经元兴奋性突触后电位(EPSP)；应用小波熵研究了EPSP所包含的信息．在计算了EPSP的小波熵、幅度、上升和下降相速率等参数并对其进行相关矩阵分析后，发现EPSP小波熵与其幅度、上升和下降相速率等参数均具有较强的正相关关系，是EPSP最具代表性的一个特征参数．进而分析了大黄酸对中枢兴奋性传递的作用，发现神经元在灌流大黄酸前后小波熵参数值变化显著．研究表明，小波熵能较全面地表征EPSP信号特征，比传统参数更具代表性，并能较灵敏地反映神经元兴奋性改变，较好地反映神经元间的信息传递．     

Stimulation parameters determine role of GABAB receptors in long-term potentiation

Blockade of GABA_B receptors was reported to improve cognitive performance in mammals. The physiological basis of this effect is poorly understood. We investigated the effect of the GABA_B receptor antagonist CGP 35348 on long-term potentiation (LTP) in the CA1 area of the hippocampus in vitro and in vivo. In vitro the effect of CGP 35348 on LTP, induced either by two non-primed tetanic stimulations or by two primed bursts of stimuli, was investigated. In the presence of 1 mM CGP 35348 LTP was significantly facilitated following two non-primed tetanic trains, but was impaired following two primed burst stimulations. In vivo LTP was induced by applying non-primed trains of stimuli of increasing duration to the Schaffer collateral/commissural fibers. The potentiation of the population spike recorded in CA1 was significantly facilitated by CGP 35348 (100 mg/kg i.v.). In conclusion these findings demonstrate that the GABA_B antagonist CGP 35348 facilitates LTP in vitro and in vivo if induced by non-primed tetanic stimulation. In vitro, the mode of stimulation determines the effect of the GABA_B antagonist on LTP.     

Transitional function of DG to CA3 in the hippocampus

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.     

Rho激酶影响大鼠海马神经元突起生长的实时成像

目的:观察Rho激酶对大鼠海马神经元突起生长的影响.方法:体外培养新生大鼠海马神经元5 d后,连续动态观察溶血性磷脂酸(lysophosphatidic acid,LPA)及Rho激酶抑制剂Y-27632对神经元突起生长的影响.结果:对照组神经元一级突起迅速生长、延伸,不断发分支,形成丰富的二级、三级突起;用LPA处理后,神经元大部分突起进行性塌陷,一级突起逐渐缩短并且变细,二级、三级突起数量减少,且较细小;而预先用Y-27632处理后再加LPA,细胞突起塌陷的现象减少,神经元的突起不断分支、延伸,一级、二级、三级突起数量较LPA组增多且长度也增加.结论:Rho激酶参与LPA诱导海马神经元突起回缩的过程,抑制Rho激酶的活性可抑制LPA诱导的突起回缩.