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1.
目的 探讨匹罗卡品诱导慢性癫痫大鼠海马齿状颗粒细胞苔藓纤维突触重建与神经营养素受体TrkB表达的关系。方法 取匹罗卡品诱导大鼠急性癫痫持续状态及慢性自发性颞叶癫痫发作期大鼠脑片,用免疫组织化学方法检测TrkB及突触体素(P38,一种突触形成标志物)在大鼠海马的表达。结果 急性癫痫持续状态诱导颗粒细胞表达TrkB一过性增高,第2次表达高峰呈现在7~30d;P38免疫反应性在齿状回内分子层则呈进行性增加,与neo-Timm显示的异常苔藓纤维出芽相一致。结论 TrkB受体激活有助于海马齿状回苔藓纤维轴突生长及突触形成从而有利于颞叶癫痫的发生。  相似文献   

2.
匹罗卡品致痫诱发大鼠齿状回颗粒细胞GAP-43 mRNA表达   总被引:1,自引:1,他引:0  
目的 研究边缘系统癫痫发作后海马颗粒细胞生长相关蛋白(GAP-43)基因表达变化。方法 建立匹罗卡品急、慢性癫痫模型,用原位杂交方法定量检测不同时间点海马颗粒细胞GAP-43mRNA表达。结果 对照组颗粒细胞几乎不表达GAP-43mRNA,匹罗卡品致病后6~12h颗粒细胞表达GAP-43mRNA增高,15~30d呈现第2次高峰。结论 成年大脑海马颗粒细胞在致痫后发生可塑性变化,GAP-43mRNA表达是癫痫大鼠大脑结构性重组(颗粒细胞苔藓纤维出芽)的重要分子机制。  相似文献   

3.
颞叶癫痫大鼠海马TrkB mRNA及其蛋白表达的动态变化   总被引:1,自引:1,他引:0  
目的 探讨颞叶癫痫发作大鼠海马TrkB mRNA及其蛋白表达的动态变化特征。方法 建立匹罗卡品(PILO)颞叶癫痢大鼠模型,应用原位杂交及免疫组织化学方法分别检测致(?)大鼠海马齿状回、CA3区及CA1区TrkB nRNA及其蛋白质表达的变化。结果 PILO致(?)后3~6 h,海马齿状回颗粒细胞层、CA1、CA3区锥体细胞层TrkB mRNA表达显著增高(P<0.01),稍后TrkB蛋白表达也随之增高。第7-30 d,TrkB mRNA及其蛋白在齿状回、CA3区呈现第二次表达增强。结论在癫(?)发作早期,TrkB表达增强,提示其可能参与急性癫痫状态的发生;后期表达增强则可能参与了海马的可塑性反应而与慢性自发性发作形成有关。  相似文献   

4.
目的 探讨氯硝西泮预处理对癫痫大鼠海马区γ-氨基丁酸A受体γ2亚单位(GABAARγ2)表达的影响.方法 60只健康雄性SD大鼠随机分为假手术组、癫痫组和氯硝西泮预处理组;癫痫组再分为6h、12 h、1 d、3d、7d、15 d和30 d7个亚组;药物预处理组再分为假预处理组、预处理6h、12h和ld亚组.药物预处理组给予氯硝西泮6 mg/(kg·d)分2次灌胃,连续5d;然后癫痫组和预处理组通过向大鼠海马C3区注射海人酸建立颞叶癫痫模型;采用免疫组化法在相应时点检测各组大鼠海马区GABAARγ2的表达.结果 与假手术组比较,癫痫组CA1区癫痫发作ld后、CA3区癫痫发作后各时间点GABAARγ2表达明显下降(P<0.05 ~0.01).与癫痫组相应亚组比较,预处理6h、12 h亚组海马CA3区及预处理ld亚组海马CA1区及CA3区GABAARγ2的表达明显增高(P<0.05~0.01).结论 氯硝西泮预处理可上调癫痫大鼠海马区GABAARγ2的表达.  相似文献   

5.
大剂量免疫球蛋白治疗癫痫的实验研究   总被引:2,自引:0,他引:2  
目的 探讨大剂量免疫球蛋白治疗癫痫的机制及其与海马区白细胞介素-2受体的关系。方法 用腹腔注射美解眠制作大鼠癫痫模型,致痫前2小时分别给予生理盐水和不同剂量的免疫球蛋白G,隔日1次,共4次。观察大鼠出现癫痫发作的潜伏期及惊厥评分,并用免疫组织化学方法观察免疫球蛋白G对癫痫大鼠海马区IL-2Rβ免疫反应阳性细胞的影响。结果 致痫前给予免疫球蛋白G组大鼠癫痫发作潜伏期较对照组大鼠延长(P<0.001),惊厥评分降低(P<0.01),海马区IL-2Rβ免疫反应阳性细胞数减少(P<0.001)。结论 大剂量免疫球蛋白对癫痫发作具有肯定的抑制作用,其机制与该疗法调节中枢神经系统免疫反应及海马区IL-2R表达,并通过IL-2R维持免疫-神经-内分泌网络的平衡有关。  相似文献   

6.
目的 探讨小鼠癫痫持续状态(Status epilepticus,SE)后海马活化素βA基因的表达与意义。方法 采用毛果芸香碱诱导的SE小鼠模型,应用逆转录-聚合酶链反应(RT-PCR)及原位杂交观察SE后海马活化素βA基因表达的动态变化;应用尼氏染色观察海马病理形态结构的变化。结果 SE后3h海马活化素SAmRNA表达即显著增高,6h达高峰,持续至约24h后开始回落,48h恢复近正常水平;活化素pAmR-NA表达最先在海马CA2及DG区上调,高峰时CA3区亦见明显表达,48h后仅CA2区仍可见阳性表达;海马活化素βA mRNA水平与神经元抗损伤力有关。结论 毛果芸香碱诱导的SE能明显上调海马活化素βA mRNA表达,其水平的上调可能有助于增强海马神经元抗兴奋性损伤的能力。  相似文献   

7.
癫痫大鼠海马中神经肽Y表达的动态观察及其作用探讨   总被引:3,自引:0,他引:3  
目的 探讨癫痫大鼠海马中神经肽 Y( NPY)表达的动态变化及其作用 ,以及外源性 NPY对癫痫的影响。方法 将 SD大鼠随机分为 4组 ,采用匹鲁卡品 ( PILO)癫痫动物模型及外源性 NPY侧脑室注入干预法 ,并以免疫组织化学染色观察 NPY的表达。结果 癫痫模型组 PILO注射后 ,门区、CA3区、CA1 区的 NPY阳性细胞数表达增多 ,1 2 h达高峰 ,以后逐渐下降 ,60 d又达一高峰 ;海马颗粒细胞层有 NPY异位表达 ,3 d时最明显 ;NPY干预组门区 NPY阳性细胞数较其对照组表达少。结论  ( 1 )癫痫发作后急性期海马 NPY表达增多及颗粒细胞层出现异位表达 ,与癫痫发作有关 ;( 2 )外源性 NPY有抗癫痫作用。  相似文献   

8.
GAD在颞叶癫痫大鼠海马内源性促痫机制中的作用   总被引:1,自引:0,他引:1  
目的:探讨GAD65、GAD67在颞叶癫痫发生后海马内源性促痫机制中的作用。方法:112只雄性SD大鼠随机分为实验组(n=70)与对照组(n=42),实验组大鼠选用海人酸腹腔注射法建立颞叶癫痫模型,对照组大鼠腹腔注射无菌生理盐水。选取腹腔注射后3小时、6小时、12小时、24小时、48小时、7天、30天为研究的时间点,颞叶海马的CA1区、CA3区、齿状回为研究部位。腹腔给药后每天观察大鼠的行为学变化,大鼠处死前进行EEG描记。用原位杂交方法检测不同时间点海马不同区域GAD65、GAD67mRNA的表达,免疫组织化学法检测GAD65、GAD67蛋白的表达。结果:实验组大鼠海马GAD65 mRNA及其蛋白的表达随时间呈逐渐增高趋势,致痫后48小时~30天,GAD65 mRNA及其蛋白表达较对照组增高(48小时P<0.05;7~30天P<0.01);海人酸致痫后6小时、24小时实验组大鼠海马的GAD67mRNA及其蛋白表达较对照组增高(分别为P<0.01、P<0.05)。结论:颞叶癫痫急性期海马GAD67表达的增高及慢性期海马GAD65表达的增高是癫痫发生后机体的内源性抗痫机制。  相似文献   

9.
癫痫大鼠海马缝隙连接蛋白43的表达及生胃酮的保护作用   总被引:1,自引:0,他引:1  
目的研究癫痫大鼠海马星形胶质细胞缝隙连接蛋白43(Connexin43,CX43)表达及缝隙连接蛋白阻滞剂生胃酮对其表达的影响。方法用免疫组化法检测癫痫发作后各时间点大鼠海马星形胶质细胞CX43免疫反应阳性表达。同时观察致痫前给予不同剂量生胃酮对大鼠海马星形胶质细胞CX43免疫反应阳性表达的影响。结果对照组大鼠海马星形胶质细胞CX43可见少量散在表达。癫痫组大鼠海马星形胶质细胞CX43表达1h即可见增加,并随时间延长而增加,72h达高峰。生胃酮各组大鼠海马星形胶质细胞CX43免疫反应阳性表达较同一时间点癫痫组低(P<0.01),且与生胃酮剂量呈负相关(P<0.01)。结论癫痫大鼠海马缝隙连接蛋白43的表达与癫痫发病机制密切相关。缝隙连接蛋白阻滞剂生胃酮影响缝隙连接蛋白43表达,具有肯定的神经保护作用。  相似文献   

10.
目的研究颞叶癫痼模型海马区神经元Aktl表达变化,探讨其在癫痫发生发展中的作用。方法采用氯化锂.匹罗卡品方法制备颞叶癫痴大鼠模型,Westernblotting检测海马区总蛋白、Quantitvone软件行灰度值分析;免疫组织化学染色观察海马各区Aktl蛋白表达变化,计数不同处理组阳性神经元数目。结果Westernblotting检测结果显示,与正常对照组相比,癫痫模型组大鼠于癫痫持续状态发作即刻海马区Aktl蛋白表达升高(t=2.445,P=0.034),并于第30天时达峰值水平(}=1.214,P=0.002),发作后24h表达水平迅速降低,并低于正常值范围(t=4.294,P=0.000),其余各测量时间点表达无明显改变;与氯化锂组相比,癫痼模型组大鼠于癫痫持续状态后1h海马区Aktl蛋白表达开始降低,24h降至最低水平(t:4.134,P=0.000),至发作48h后开始逐渐升高(t=2.481,P=0.002),并于发作第7天时升至氯化锂组水平。免疫组织化学染色显示,癫痫持续状态发作后海马CA3区Aktl蛋白表达阳性神经元数目立即增加,12h达高峰(t=16.586,P:0.000),48h减少并降至正常值水平(t=0.357,P=0.089),发作后第10天再次增加(t=3.123,P=0.000),于第30天时阳性神经元数目再次达峰值水平(t=18.339,P=0.000),第50天开始恢复至正常值水平(t=3.219,P=0.000);氯化锂组仅海马CA3区Aktl蛋白表达于实验初始(0h)升高并高于正常对照组(P〈0.05),海马CA1和CA2区Aktl蛋白表达变化组间差异均无统计学意义(P〉O.05)。结论海马及海马CA3区Aktl蛋白表达均呈现癫疝持续状态后升高、降低、再升高的动态过程,提示可能存在神经元保护作用,对抗细胞凋亡、促进细胞存活。  相似文献   

11.
Summary This study concerns the expression of synaptophysin in the hippocampal formation of normal controls, of patients with Alzheimer's disease (AD) and of patients with parkinsonism-dementia complex on Guam (P-D complex). A monoclonal antibody was used to visualize synaptophysin, an integral component of presynaptic vesicle membranes. In the normal controls, a strong synaptophysin immunoreactivity was seen in the stratum pyramidale, stratum radiatum and stratum lacunosum-moleculare of the hippocampus proper, in the subiculum and in the molecular layer of the dentate gyrus. In the dentate gyrus molecular layer, the reaction product was distributed in a laminar fashion. By contrast, in AD and in P-D complex a significant decrease in immunoreactivity was observed in all hippocampal strata, and especially of the hippocampal subfield CA1 and the subiculum. In both diseases, synaptophysin expression was also diminished in the molecular layer of the dentate gyrus of all patients examined, with the inner portion exhibiting almost normal and the outer portion a strikingly reduced synaptophysin immunoreactivity.  相似文献   

12.
In the present study, we performed an analysis of tandem of P domains in a weak inwardly rectifying K+ channel (TWIK)-related acid-sensitive K+ (TASK)-1 channel immunoreactivity in the rat hippocampal complex following pilocarpine-induced status epilepticus (SE). In control animals, TASK-1 immunoreactivity was strongly detected in astrocytes in the hippocampal complex. One day after SE, TASK-1 immunoreactivity in astrocytes was markedly reduced only in the molecular layer of the dentate gyrus. One week after SE, loss of astrocytes was observed in the molecular layer of the dentate gyrus. At this time point, TASK-1 immunoreactive cells were detected mainly in the subgranular region. These cells had bipolar, elongated cell bodies with fusiform-shaped nuclei and showed vimentin immunoreactivity. Four weeks after SE (when spontaneous seizure developed), typical reactive astrogliosis was observed in the dentate gyrus and the CA1 region. Almost no astrocytes in the molecular layer showed TASK-1 immunoreactivity, whereas astrocytes in the CA1 region showed strong TASK-1 immunoreactivity. These findings indicate that, after SE, TASK-1 immunoreactivity was differentially altered in astrocytes located in different regions of the hippocampal complex, and these changes were caused by astroglial degeneration/regeneration. Therefore, alteration in TASK-1 immunoreactivity may contribute to acquisition of the properties of the epileptic hippocampal complex.  相似文献   

13.
Summary The expression of mRNA coding for AMPA selective glutamate (Glu) R2 receptor and kainate selective GluR5 receptor was studied in the rat hippocampal formation in two animal models of limbic seizures evoked by systemic administration of pilocarpine (400 mg/kg ip) or kainate (15 mg/kg ip). As shown by an in situ hybridization study, pilocarpine decreased the GluR2 flip mRNA level in CA1 and CA3 areas of the hippocampus after 3h and kainate after 24 h, e.g. at the time preceding neuronal degeneration. No changes in the GluR2 flop or GluR5 mRNA level were found in those regions. In the dentate gyrus, resistant to neurodegeneration, pilocarpine and kainate differentialy affected the expression of GluR2 and GluR5 mRNAs. After 72 h pilocarpine, but not kainate, increased the GluR2 flop mRNA level and decreased the flip one, which suggests attenuation of the GluR2 sensitivity. On the other hand, kainate, elevated the GluR2 flip and GluR5 mRNA level in the dentate gyrus after 72 h. All in all the above data suggest that changes in the GluR2 gene expression may play some role in the neuronal damage to vulnerable areas (CA1, CA3). However, differences in the kainate- and pilocarpine-induced changes in the dentate gyrus at the late time points indicate that alterations in the stoichiometry of GluR2 forms or GluR5 gene expression in this brain region are not a common causal factor responsible for delayed neuronal hyperexcitability.  相似文献   

14.
戊四氮点燃大鼠模型海马结构内突触体素的变化   总被引:6,自引:0,他引:6  
目的:探讨癫痫时海马结构的可塑性。方法:利用图像分析分析仪戊四氮诱导的大鼠点燃模型海马CA1、CA3区及齿状回区突触体素的阳性免疫反应产物的光密度值(OD值)。结果:点燃组海马人各部突触体素阳性免疫反应产物光密度值较对照组增加,尤以CA3区苔藓纤维层的齿状回分子层内带为甚。结论:突触体素含量的变化一方面是点燃的结果,另一方面也可能导致点燃维持的分子学基础。  相似文献   

15.
The cadherin family consists of several homophilic adhesion molecules that, together with their intracellular binding partners the catenins, are known to mediate axonal navigation, target recognition, and synapse formation during development. Here, we have examined the potential role of these molecules in axonal sprouting induced in the adult brain. Over a period of 3 to 60 days, an episode of pilocarpine-induced status epilepticus (SE) led to sprouting of hippocampal mossy fibers both into the CA3 pyramidal cell layer and the inner molecular layer of the dentate gyrus (DG). We found focal up-regulation of N-cadherin, beta-catenin, and alpha-catenin immunoreactivity within segments of the CA3 pyramidal cell layer with pronounced neuron loss that was associated with the development of mossy fiber sprouting. In contrast, expression of these 3 molecules was unaltered in the DG molecular layer despite mossy fiber sprouting in this area. The levels of E-cadherin immunoreactivity were altered prior to the detection of mossy fiber sprouting, with a general reduction in the neuropil and increased expression in CA1/CA3 pyramidal cell somata. Our results imply that members of the cadherin/catenin families undergo specific spatiotemporal patterns of regulation, which may be important in axon target recognition and synapse formation during lesion-induced sprouting.  相似文献   

16.
Neuronal fibres of the hippocampal formation of normal and chronic epileptic rats were investigated by fluorescent tracing methods using the pilocarpine model of limbic epilepsy. Two months after onset of spontaneous limbic seizures, hippocampal slices were prepared and maintained in vitro for 10 h. Small crystals of fluorescent dye [fluorescein (fluoro-emerald) and tetramethylrhodamine (fluoro-ruby)] were applied to different hippocampal regions. The main findings were: (i) in control rats there was no supragranular labelling when the mossy fibre tract was stained in stratum radiatum of area CA3. However, in epileptic rats a fibre network in the inner molecular layer of the dentate gyrus was retrogradely labelled; (ii) a retrograde innervation of area CA3 by CA1 pyramidal cells was disclosed by labelling remote CA1 neurons after dye injection into the stratum radiatum of area CA3 in chronic epileptic rats; (iii) labelling of CA1 neurons apart from the injection site within area CA1 was observed in epileptic rats but not in control animals; and (iv), a subicular-hippocampal projection was present in pilocarpine-treated rats when the tracer was injected just below the stratum pyramidale of area CA1. The findings show that fibre rearrangement in distinct regions of the epileptic hippocampal formation can occur as an aftermath of pilocarpine-induced status epilepticus.  相似文献   

17.
目的探讨颞叶癫痫发作后海马EphA5及ephrinA3基因的表达变化和轴突出芽的关系。方法建立氯化锂-匹罗卡品颞叶癫痫大鼠模型,利用原位杂交方法检测致痫后12h、24h、7d、15d、30d、60d海马CA3区、CA1区EphA5及ephrinA3 mRNA的表达,快速Golgi染色观察CA1区的轴突出芽。结果致痫后,EphA5 mRNA在CA3区表达下调,ephrinA3 mRNA在CA1区表达下调,均在7d降至最低点,与对照组相比差异有显著意义(P<0.01),此后逐渐回升,但15d时仍低于对照组(P<0.05),在30d和60d与对照组相比差异无统计学意义(P>0.05)。快速Golgi染色显示,对照组大鼠CA1区轴突走行正常,匹罗卡品致大鼠SE后7dCA1区锥体细胞层出现显著增多的轴突染色。结论CA3区的EphA5和CA1区的ephrinA3的表达下调可能与CA1区的轴突出芽、突触重建有关。  相似文献   

18.
《中国神经再生研究》2016,(8):1254-1259
Recent evidence exists that glucose transporter 3 (GLUT3) plays an important role in the energy metabo-lism in the brain. Most previous studies have been conducted using focal or hypoxic ischemia models and have focused on changes in GLUT3 expression based on protein and mRNA levels rather than tissue levels. In the present study, we observed change in GLUT3 immunoreactivity in the adult gerbil hippocampus at various time points after 5 minutes of transient forebrain ischemia. In the sham-operated group, GLUT3 immunoreactivity in the hippocampal CA1 region was weak, in the pyramidal cells of the CA1 region in-creased in a time-dependent fashion 24 hours after ischemia, and in the hippocampal CA1 region decreased signiifcantly between 2 and 5 days after ischemia, with high level of GLUT3 immunoreactivity observed in the CA1 region 10 days after ischemia. In a double immunolfuorescence study using GLUT3 and gli-al-ifbrillary acidic protein (GFAP), we observed strong GLUT3 immunoreactivity in the astrocytes. GLUT3 immunoreactivity increased after ischemia and peaked 7 days in the dentate gyrus after ischemia/reperfu-sion. In a double immunolfuorescence study using GLUT3 and doublecortin (DCX), we observed low level of GLUT3 immunoreactivity in the differentiated neuroblasts of the subgranular zone of the dentate gyrus after ischemia. GLUT3 immunoreactivity in the sham-operated group was mainly detected in the subgran-ular zone of the dentate gyrus. These results suggest that the increase in GLUT3 immunoreactivity may be a compensatory mechanism to modulate glucose level in the hippocampal CA1 region and to promote adult neurogenesis in the dentate gyrus.  相似文献   

19.
Calcium-binding proteins calbindin D28k (CaBP) and parvalbumin (PV) were localized in neurons of the monkey hippocampal formation. CaBP immunoreactivity is present in all granule cells and in a large proportion of CA1 and CA2 pyramidal neurons, as well as in a distinct population of local circuit neurons. In the dentate gyrus, CaBP-immunoreactive nongranule cells are present in the molecular layer and in the hilar region, but they do not include the pyramidal basket cells at the hilar border. In the Ammon's horn, CaBP-positive, nonpyramidal neurons are more frequent in the CA3 area than in any other parts of the hippocampal formation. They are concentrated in the strata oriens and pyramidale of areas CA1-3, whereas only a few small neurons were found in the strata lucidum and radiatum of CA3 and in the stratum moleculare of the CA1 area. PV is exclusively present in local circuit neurons both in the dentate gyrus and in Ammon's horn. In the dentate gyrus the presumed basket cells at the hilar border exhibit PV immunoreactivity. In the hilar region and molecular layer only a relatively small number of cells are immunoreactive for PV. Most of these PV-positive cell bodies are located in the inner half of the molecular layer, with occasional horizontal cells at the hippocampal fissure. In Ammon's horn, strata oriens and pyramidale of areas CA1-3 contain a large number of PV-positive cells. There are no PV-immunoreactive cells in the strata lucidum, radiatum, or lacunosum moleculare. The CaBP- and PV-containing neurons form different subpopulations of cells in the monkey hippocampal formation. With the exception of a basket cell type in the monkey dentate gyrus, the CaBP- and PV-positive cell types were found to be remarkably similar in rodents and primates.  相似文献   

20.
目的研究卡马西平对成年癫大鼠海马齿状回新生神经元的影响及其与空间记忆之间的关系。方法采用氯化锂和匹罗卡品联合诱导大鼠癫模型,利用5-溴脱氧尿苷嘧啶与神经元核性蛋白双标记观察海马齿状回内源性神经前体细胞分化为成熟神经元的情况;利用行为学分析评价大鼠的空间记忆。结果 (1)卡马西平可增加癫大鼠海马齿状回新生成熟神经元的数量(P<0.05);(2)卡马西平对癫大鼠的空间记忆有明显改善作用(P<0.01)。结论卡马西平增加癫大鼠海马齿状回新生成熟神经元形成,是其改善癫大鼠空间记忆的可能机制之一。  相似文献   

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