小胶质细胞与癫痫的关系研究进展

正癫痫是一种常见的神经系统疾病。目前,全球约有癫痫病人5 000万,我国约有900万,而且每年有40～50万的新发病人~([1])。反复的癫痫发作导致病人发育迟缓、认知障碍,以及精神行为异常等。癫痫病人不仅生活质量低下,而且死亡年龄比一般人群     

癫痫细胞模型的建立及应用

癫痫是神经系统的第二大疾病,癫痫模型是癫痫相关研究的重要工具,其中细胞模型具有造模简单、干扰因素少、结果直观等优点,且从单细胞培养向多细胞共培养发展,以在维持其上述优点的同时更大程度上地还原其在体环境,也满足了不同的实验需求。在抗癫痫发作药物、癫痫病理生理学以及生物标志物等研究中有广泛的应用。癫痫细胞模型可初步筛选可能抗癫痫发作的药物,而已被证实的抗癫痫发作药物也可进一步探索其作用机制。癫痫病理生理学机制复杂,在细胞模型中可针对某种机制进行独立研究,排除其他因素的干扰。生物标志物对于疾病临床有极大意义,细胞模型可对癫痫的生物标志物进行初步筛选和验证。本文概述了常用癫痫细胞模型的细胞系、培养体系、诱导方法及应用,可作为选择癫痫模型时的参考依据。     

大脑可塑性与癫痫形成机制

近年来 ,随着神经科学的发展 ,对癫痫发病机制的研究已逐渐集中到癫痫大脑是如何在没有致癫刺激的情况下启动反复惊厥发作。现在研究者认为癫痫患者和癫痫动物模型一样 ,在癫痫形成过程中 ,大脑内神经元之间形成异常的突触联系 ,建立病理性神经环路 ,导致大脑兴奋性增强 ,这种与癫痫相关的异常神经环路的形成也是大脑可塑性变化过程。大脑可塑性是指大脑按一定规律或模式建立神经连接的形式 ,具有一定特异性。一切有异于正常或特异性的模式都可说具有可塑性的。广义地说 ,凡有异于神经系统正常活动模式的情况都可列入可塑性范围。1　大脑可…     

降纤酶对大鼠局灶性脑缺血血管内皮细胞超微结构及内皮细胞凋亡的影响

目的 探讨降纤酶对缺血性脑水肿病理过程中血脑屏障（BBB）内皮细胞的保护作用以及其对内皮细胞凋亡的影响。方法 选用Wistar雄性大鼠42只，体重250－300g，鼠龄3－4个月，随机分成降纤酶组、盐水对照组和假手术组，参考Longa等方法建立大鼠大脑缺血动物模型，彩和电观察大鼠BBB的超微结构和TUNEL试剂盒检测内皮细胞的凋亡。结果 通过电镜观察发现降纤酶组的毛细血管内皮细胞膜完整，水肿较轻，其损伤程度明显较对照组轻。降纤酶组在缺血6h和缺血24h随缺血时间延长缺血中心区凋亡细胞数量减少，而缺血半影区凋亡细胞数量增加，其凋讯细胞数量明显少于盐水对照组同一时期值。结论 降纤酶对脑缺血的血管内皮细胞及BBB具有明显的保护作用。     

谷氨酸转运体与癫痫关系的研究进展

谷氨酸(Glutamate,Glu)作为哺乳动物中枢神经系统(Central nerve system,CNS)中最重要的兴奋性神经递质,对CNS发育和正常脑功能发挥起调节作用。Glu经突触前膜释放到突触间隙后,通过作用于谷氨酸受体发挥各种各样的生理功能,发挥作用后立即被位于神经胶质细胞和神经元胞浆     

红藻氨酸诱导慢性颞叶癫痫鼠脑海马胶质细胞增生和突触重建的研究

目的 探讨红藻氨酸诱导的慢性颞叶癫痫鼠脑海马突触重建及胶质增生与颞叶癫痫发病机制的关系。方法 采用Neo-Timm银染观察苔藓纤维出芽及突触重建;免疫组织化学染色观察质原纤维酸性蛋白（GFAP）和神经细胞粘附分子（NCAM）表达水平。结果 鼠脑海马注入红藻氨酸后,双侧海马区均出现神经元脱失、突触重建及胶质细胞增生,注射侧以CA3区、门区明显,CA1区受累较轻;对侧CA1区、门区明显,CA3区相对较轻,其程度随存活时间延长而加重。结论 鼠脑海马内注射红藻氨酸引起的神经元脱失、反应性胶质细胞增生和神经元可塑性改变,可能与形成异常神经元放电环路,最终诱发癫痫发作有关。     

炎性反应与癫痫

近年来研究显示炎性反应与癫痫的发生发展密切相关。炎性反应使血脑屏障完整性被破坏,通透性增加,白细胞浸润;胶质细胞活化、增生,分泌大量的促炎性细胞因子并上调其相关受体,这些反应进一步使神经元兴奋性增高,诱导癫痫发作。炎性反应产生的细胞兴奋性毒性,诱发神经元死亡,破坏脑组织,形成海马硬化等病理改变。炎性反应还使病程迁延反复,产生对常规抗癫痫药物的抵抗等。本文主要对炎性反应与癫痫发生、发展的关系及相关治疗做一综述。     

炎性反应与癫痫

越来越多的研究显示炎性反应与癫痫的发病密切相关。在炎性反应过程中,血脑屏障完整性被破坏,通透性增加,白细胞浸润;胶质细胞活化、增生,分泌大量的促炎性细胞因子并上调其相关受体。这些反应进一步使神经元兴奋性增高,诱导癫痫发作;产生细胞兴奋性毒性,诱发神经元死亡,破坏脑组织,形成海马硬化等病理改变;使病程迁延反复,产生对常规抗癫痫药物的抵抗等。本文主要对炎性反应与癫痫发生、发展的关系及相关治疗做一综述。     

星形胶质细胞调节突触可塑性机制的研究进展

在成年脑组织细胞中占90％的胶质细胞一直被认为是简单的大脑填料，支撑和营养神经元以及清除突触间隙中过多的离子和神经递质。但近年研究结果表明神经胶质细胞与神经元间的关系远非如此简单，这些新揭示的功能包括调节突触数目、结构和功能变化，调节神经传导和神经分泌等。在脑发育成熟、学习记忆等生理过程和脑损伤后神经功能恢复过程中突触数目、形态结构和功能会发生某些变化的现象，我们称之为突触可塑性。现就星形胶质细胞（As—trocyte，AS）调节突触可塑性机制的研究进展综述如下。     

星型细胞在癫痫发病机制中作用的研究进展

近年研究表明 ,反应性胶质增生是癫痫的显著病理形态学特征。星形细胞在发育过程中起引导和支持神经元迁移 ,保持神经元的微环境 ,通过免疫原介导细胞及调节免疫反应等作用。此外星形细胞在癫痫的发生及发展过程中扮演重要角色。     

痫灶切除方式对顽固性癫痫手术疗效的影响

目的：探讨影响手术治疗顽固性癫痫疗效的因素。研究痫灶切除方式、病灶存在与否与疗效的关系。方法：对1992年以来术后随访3件以上的51例顽固性癫痫进行回顾性分析。采取Ridit分析,比较痫灶完全切除组（20例）与痫灶不完全切除组（31例）、占位组（28例）与非占位组（23例）的疗效。结果：全组显效率达88．23％。1．痫灶完全切除组的疗效较痫灶不完全切除组好（P＜0．01）;2．占位组与非占位组疗效无差别（P＞0．05）。结论：痫灶切除程度对顽固性癫痫手术疗效有重要影响,有无占位性病灶对疗效影响不大,进一步说明了病灶与痫灶是二个不同的概念。把痫灶切除与否作为影响疗效的主要因素更具合理性。     

Axon terminals of GABAergic chandelier cells are lost at epileptic foci

Axon terminals of chandelier cells were analyzed in monkeys with cortical focal epilepsy produced by alumina gel to determine if this type of GABAergic terminal is lost at epileptic foci. These terminals form a dense plexus with the axon initial segments of pyramidal neurons, especially those in layers II and III. Axon initial segments of pyramidal neurons were traced for at least 40 μm in serial thin sections and beyond this point were observed to become myelinated. In single sections, 10–15 axon terminals were found to form symmetric synapses throughout the entire lenght of the axon initial segments from nonepileptic preparations and were observed to synapse with only these structures and not adjacent dendrites or spines. In epileptic cortex, the axon initial segments of pyramidal neurons were apposed by glial profiles that contained clusters of filaments typical of reactive astrocytes. Only a few, small axon terminals were observed to form symmetric synapses with these axon initial segments. Thus, the chandelier cell axons appeared to degenerate in epileptic cortex. The highly strategic site of GABAergic inhibitory synapses on axon initial segments suggests that they exert a strong influence on the output of pyramidal cells. The near absence of these chandelier cell axons in epileptic foci most likely contributes to the hyperexcitability of neurons.     

Synaptic and blood-brain barrier structural changes in a rat epilepsy model induced by coriaria lacton

BACKGROUND: Structural and functional synaptic changes, as well as blood-brain barrier (BBB) changes, affect the micro-environment of nervous tissue and excitation, both of which play an important role in epilepsy.OBJECTIVE: To observe synaptic and BBB ultrastructural changes in the motor cortex of a rat epilepsy model induced by coriaria lacton, and to investigate the synaptic and BBB effects on the mechanism of epilepsy.DESIGN: A randomized controlled animal experiment.SETTING: Department of Histology and Embryology, Luzhou Medical College; and Electron Microscopy Laboratory, Luzhou Medical College.MATERIALS: Twenty healthy male Sprague Dawley rats, aged 8 weeks, were chosen for this study. The rats weighed (280 ± 50) g and were supplied by the Experimental Animal Center of Luzhou Medical College. Experimentation was performed in accordance with the ethical guidelines for the use and care of animals. The animals were randomly divided into a control group and an epilepsy group, with 10 rats in each group. METHODS: This study was performed at the Department of Histology and Embryology, and Electron Microscopy Laboratory, Luzhou Medical College between February and December 2006. According to the protocol, the epilepsy group was injected with 10 μL/100 g coriaria lacton into the lateral ventricles to establish an epileptic model. The control group rats were not administered anything. Eight days after the model was established, all rats were anesthetized with ether. The motor cortex was removed and sectioned into ultrathin sections. Synaptic and BBB ultrastructural changes were observed by electron microscopy. MAIN OUTCOME MEASURES: ①Structural changes of three different parts of the synapses, synaptic cleft width, postsynaptic density thickness, proportion of perforation synapses, curvature of synaptic interface, and length of active zones. ②Capillary and BBB changes (endothelium, basement membrane, pericyte, and the astrocyte endfeet).RESULTS: ①Curvature of synaptic interface, length of active zones, thickness of postsynaptic density, and percentage of perforation synapses increased significantly. ②There was significant edema in the endothelium, basement membrane, and the pericyte of the epilepsy group; the electron density of the basement membrane was reduced.CONCLUSION: ①The coriaria lacton treatment altered synaptic ultrastructure, as well as BBB characteristics, in the epileptic rat model, and also improved synaptic transmission efficiency, as well as BBB permeability; ②Synaptic and BBB ultrastructural changes might play an important role in the mechanism of epilepsy.     

Synaptic and blood-brain barrier structural changes in a rat epilepsy model induced by coriaria lacton**★ Replication experiment with animals

BACKGROUND： Structural and functional synaptic changes, as well as blood-brain barrier （BBB） changes, affect the micro-environment of nervous tissue and excitation, both of which play an important role in epilepsy. OBJECTIVE： To observe synaptic and BBB ultrastructural changes in the motor cortex of a rat epilepsy model induced by coriaria lacton, and to investigate the synaptic and BBB effects on the mechanism of epilepsy. DESIGN： A randomized controlled animal experiment. SETTING： Department of Histology and Embryology, Luzhou Medical College; and Electron Microscopy Laboratory, Luzhou Medical College. MATERIALS： Twenty healthy male Sprague Dawley rats, aged 8 weeks, were chosen for this study. The rats weighed （280 ± 50） g and were supplied by the Experimental Animal Center of Luzhou Medical College. Experimentation was performed in accordance with the ethical guidelines for the use and care of animals. The animals were randomly divided into a control group and an epilepsy group, with 10 rats in each group. METHODS： This study was performed at the Department of Histology and Embryology, and Electron Microscopy Laboratory, Luzhou Medical College between February and December 2006. According to the protocol, the epilepsy group was injected with 10 μ L/100 g coriaria lacton into the lateral ventricles to establish an epileptic model. The control group rats were not administered anything. Eight days after the model was established, all rats were anesthetized with ether. The motor cortex was removed and sectioned into ultrathin sections. Synaptic and BBB ultrastructural changes were observed by electron microscopy. MAIN OUTCOME MEASURES： （1）Structural changes of three different parts of the synapses, synaptic cleft width, postsynaptic density thickness, proportion of perforation synapses, curvature of synaptic interface, and length of active zones. （2）Capillary and BBB changes （endothelium, basement membrane, pericyte, and the astrocyte endfeet）. RESULTS： （1）Curvature of sy     

Upregulation of dysbindin in temporal lobe epileptic foci of human and experimental animals

The gene encoding dystrobrevin-binding-protein-1 (dysbindin) is expressed in many areas of the central nervous system and plays a role in intracellular vesicle trafficking, synaptic vesicle trafficking, and neurotransmitter release. At a cellular level, dysbindin is thought to mediate presynaptic glutamatergic transmission. Using Western blotting and immunofluorescence, we investigated dysbindin expression in brain tissues of the patients with temporal lobe epilepsy (TLE) and rats with TLE (lithium chloride pilocarpine model) to explore its possible role in epileptogenesis. Twenty-five samples of temporal neocortex from patients undergoing surgery for drug-refractory TLE epilepsy and 10 histologically normal temporal lobes tissues from control subjects were used in our study. We also examined dysbindin expression in the hippocampus and adjacent cortex from experimental Sprague-Dawley rats. Dysbindin was expressed in the cytoplasm of neurons from epileptic specimens, and levels of dysbindin proteins were significantly increased in patients with TLE. Dysbindin was also expressed in the neurons of the hippocampus and adjacent cortex from experimental and control rats. Western blotting of rat brain tissue showed that dysbindin was upregulated gradually from 6 h after kindling. Maximal expression was seen around 2 months in chronic epileptic phase. These results demonstrated that the increased expression of dysbindin might play a role in the pathogenesis of drug-refractory TLE.     

在偶极子定位下显微手术治疗难治性癫痫30例临床分析

目的探讨偶极子定位方法在药物难治性癫痫术前致痫灶定位研究中的作用和准确性。方法对30例药物难治性癫痫患者的致痫灶进行术前偶极子定位,术中以皮层及深部电极加以验证,依据验证结果比较继发性癫痫和原发性癫痫偶极子定位的准确性,并对病灶、致痫灶进行手术处理,术后随访并分别比较继发性癫痫和原发性癫痫的手术治疗效果。结果偶极子对继发性癫痫致痫灶定位的准确性要高于原发性癫痫,经卡方检验,x±s=12.470,P=0.001统计学有显著性差异;两者的治疗结果,P=0.143差异没有显著性。结论偶极子定位是一种无创性的致痫灶定位方法,对继发性癫痫术前致痫灶定位准确,手术效果满意;对原发性癫痫或致痫灶多发、弥散,偶极子定位技术存在一定的局限性。     

Ultrastructural studies of the neurovascular unit reveal enhanced endothelial transcytosis in hyperglycemia-enhanced hemorrhagic transformation after stroke

AimsPre‐existing hyperglycemia (HG) aggravates the breakdown of blood–brain barrier (BBB) and increases the risk of hemorrhagic transformation (HT) after acute ischemic stroke in both animal models and patients. To date, HG‐induced ultrastructural changes of brain microvascular endothelial cells (BMECs) and the mechanisms underlying HG‐enhanced HT after ischemic stroke are poorly understood.MethodsWe used a mouse model of mild brain ischemia/reperfusion to investigate HG‐induced ultrastructural changes of BMECs that contribute to the impairment of BBB integrity after stroke. Adult male mice received systemic glucose administration 15 min before middle cerebral artery occlusion (MCAO) for 20 min. Ultrastructural characteristics of BMECs were evaluated using two‐dimensional and three‐dimensional electron microscopy and quantitatively analyzed.ResultsMice with acute HG had exacerbated BBB disruption and larger brain infarcts compared to mice with normoglycemia (NG) after MCAO and 4 h of reperfusion, as assessed by brain extravasation of the Evans blue dye and microtubule‐associated protein 2 immunostaining. Electron microscopy further revealed that HG mice had more endothelial vesicles in the striatal neurovascular unit than NG mice, which may account for their deterioration of BBB impairment. In contrast with enhanced endothelial transcytosis, paracellular tight junction ultrastructure was not disrupted after this mild ischemia/reperfusion insult or altered upon HG. Consistent with the observed increase of endothelial vesicles, transcytosis‐related proteins caveolin‐1, clathrin, and hypoxia‐inducible factor (HIF)‐1α were upregulated by HG after MCAO and reperfusion.ConclusionOur study provides solid structural evidence to understand the role of endothelial transcytosis in HG‐elicited BBB hyperpermeability. Enhanced transcytosis occurs prior to the physical breakdown of BMECs and is a promising therapeutic target to preserve BBB integrity.     

PET-CT联合神经导航在难治性癫痫术中致痫灶定位中的应用

目的探讨PET-CT在难治性癫痫手术致痫灶定位应用中的准确性。方法回顾性分析80例2016-03—2018-05在郑州大学第二附属医院治疗的难治性癫痫患者,所有患者均已明确口服抗癫痫药物效果较差,经磁共振检查均为阴性,经24 h视频脑电监测结果回示有明显异常,根据是否行PET-CT检查分组,其中40例行PET-CT检查的患者设定为观察组,使用神经外科导航融合PET-CT影像学数据行术前定位癫痫灶;未行PET-CT检查的40例患者设定为对照组。2组患者术中均使用皮层脑电图监测定位致痫灶,并通过手术切除癫痫灶,观察术后癫痫症状的缓解情况。结果观察组治疗效果明显优于对照组(P<0.05);且观察组术后癫痫缓解情况、术中损伤明显优于对照组(P<0.05)。结论PET-CT联合神经外科导航可优化难治性癫痫手术的过程,在整个治疗过程起到关键作用。     

Pathogenesis of epileptic seizures and epilepsy after stroke

Stroke is an important cause of seizures and epilepsy in adults, particularly among the elderly. The incidence of stroke increases yearly as life expectancy increases and the number of patients with post-stroke seizures and epilepsy is also rising. Post-stroke epilepsy accounts for nearly 50% of newly diagnosed epilepsy among patients over 60 years of age. With increasing stroke awareness and advanced treatments, increased attention is paid to post-stroke seizures and epilepsy including its diagnosis and treatment. There has been a plethora of research on the pathogenesis of seizures and epilepsy after stroke. And thus, the research advances in the pathogenesis and related therapeutic targets of post-stroke seizures and epilepsy will be reviewed in this article.     

癫痫病人棘波灶的电镜改变

报告２５例癫痫患者在进行手术治疗时，皮层脑电监测下，取棘波最明显最多的大脑皮层做电镜观察，同时对８例病人的胼胝体也做电镜观察。结果发现超微结构下的神经细胞，突触与神经毡，星形胶质细胞，毛细血管及髓鞘均有不同程度的病理变化，突触前轴突末梢及突触后树突均发生不同程度的水肿，尤以突触后树突水肿明显并伴有突触前轴突末梢突触小泡的聚集增多。这些同癫痫的发生有密切关系，在癫痫发病和脑电棘波形成中具有重要意义，本文对这些改变进行分析讨论。