人参皂甙Rd对颞叶癫大鼠学习记忆能力及海马5-HT表达的影响

目的研究人参皂甙Rd对氯化锂-匹罗卡品点燃颞叶癫(temporal lobe epilepsy,TLE)大鼠学习记忆能力及海马5-HT表达的干预作用。方法建立氯化锂-匹罗卡品点燃颞叶癫大鼠模型,将30只造模成功的颞叶癫大鼠随机分为TLE组(生理盐水10ml/kg腹腔注射,15只)及GSRd干预组(人参皂甙Rd2mg/kg腹腔注射,15只),另选15只大鼠作为正常对照组;采用Morris水迷宫及免疫组化染色分别检测各组大鼠学习记忆能力及海马5-HT表达水平。结果与正常对照组比较,TLE组大鼠学习记忆能力下降,海马5-HT表达明显减少(P0.05);与TLE组比较,GSRd干预组可显著提高大鼠学习记忆能力及海马5-HT的表达水平(P0.05)。结论人参皂甙Rd可能通过增加海马5-HT的表达来提高颞叶癫大鼠学习记忆能力。     

卡马西平对匹罗卡品诱导成年癫间疒大鼠海马齿状回神经前体细胞增殖的影响

目的研究卡马西平对成年癫大鼠海马齿状回内源性神经前体细胞增殖的影响。方法采用氯化锂和匹罗卡品联合诱导大鼠癫模型,将癫大鼠随机分为癫对照组和癫卡马西平组,正常大鼠随机分为正常对照组和正常卡马西平组。癫对照组和正常对照组给以蒸馏水灌胃,同时癫卡马西平组和正常卡马西平组给予卡马西平灌胃。于灌胃后第6d腹腔注射5-溴脱氧尿苷嘧啶(BrdU)标记海马齿状回的内源性神经前体细胞的增殖情况;用免疫组化方法观察各组大鼠在注射BrdU后第1d、第7d齿状回BrdU阳性细胞数量的表达。结果①注射BrdU后第1d,癫对照组大鼠海马齿状回BrdU阳性细胞数较正常对照组明显增加(P<0.01),癫卡马西平组大鼠海马齿状回BrdU阳性细胞数较癫对照组减少(P<0.05);②注射BrdU后第7d,癫对照组大鼠海马齿状回BrdU阳性细胞数较正常对照组明显增加(P<0.01),癫卡马西平组大鼠海马齿状回BrdU阳性细胞数较癫对照组明显减少(P<0.05)。结论卡马西平抑制癫大鼠海马齿状回内源性神经前体细胞增殖。     

甘松治疗戊四氮致大鼠的实验性研究

目的观察甘松对戊四氮致大鼠的疗效。方法将50只Wistar大鼠随机分为5组,每组各10只,分别为正常对照组、模型组、甘松治疗组、丙戊酸钠治疗组和甘松合并丙戊酸钠治疗组;采用腹腔注射戊四氮制作建立癫模型;观察各组大鼠行为学及脑电图、NSE(神经元特异性烯醇化酶)浓度变化。结果与模型组比较,甘松治疗组、丙戊酸钠治疗组、甘松合并丙戊酸钠组可明显减轻大鼠样发作程度,减少发作频率和持续时间,改善大鼠皮层脑电图,降低脑脊液神经元特异性烯醇化酶浓度,其中以甘松合并丙戊酸钠组最为明显。结论甘松对戊四氮致大鼠具有一定的抗癫及脑保护作用,与丙戊酸钠联用有协同作用。     

银杏叶提取物对戊四氮致大鼠海马内NMDA受体和HSP70表达的影响

目的探讨银杏叶提取物抗癫的分子生物学机制。方法在SD大鼠腹腔内注射戊四氮(PTZ)诱发大鼠惊厥急性发作,制作癫模型。应用免疫组化技术观察银杏叶提取物(GBE)对点燃癫大鼠海马内NMDA受体和HSP70表达的影响。结果戊四氮致组大鼠海马内NMDA受体表达明显高于正常对照组,银杏叶提取物干预组明显低于戊四氮致组,银杏叶提取物干预组与正常对照组之间差异无显著性意义。戊四氮致组大鼠海马内HSP70表达明显高于正常对照组,银杏叶提取物干预组明显高于戊四氮致组。结论银杏叶提取物可降低癫大鼠海马内NMDA受体的表达,其可能通过此种机制来抑制癫的发生和发展。银杏叶提取物可增加癫大鼠海马内HSP70的表达,以此来减轻癫发作后所致的神经元损伤。     

AG490对氯化锂-匹罗卡品致癫大鼠星形胶质细胞活化及癫的影响

目的探讨匹罗卡品致癫大鼠海马肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的表达、星形胶质细胞活化及JAK/STAT信号转导通路在颞叶癫发作中的作用。方法应用腹腔注射氯化锂-匹罗卡品(PILO)的方法建立颞叶癫模型,应用JAK/STAT信号转导通路特异性抑制剂AG490进行腹腔注射建立干预模型组;用Western blotting方法测定大鼠海马匀浆后TNF-α表达水平的变化,用免疫荧光观察AG-490阻滞JAK/STAT通路后对大鼠海马TNF-α表达水平与星形胶质细胞活化及癫发作的影响。结果 (1)PILO致癫模型组有80.00%(32/40)的大鼠达Racine分级Ⅳ级以上发作;10.00%(4/40)的雄性大鼠死亡;10.00%(4/40)的雄性大鼠未达Racine分级Ⅳ级发作,模型成功率为80.00%;1月后有自发发作者8只(25.00%8/32)。AG490干预组雄性大鼠Ⅳ级以上发作的发生率为75.00%(30/40);病死率为7.50%(3/40);17.50%(7/40)的雄性大鼠未达Ⅳ级发作,模型成功率为75%;1月后有自发发作者1只(3.3%1/30),AG490组Ⅳ级及以上发作及自发发作数与PILO致癫模型组比较,有显著性差异(P<0.05);(2)PILO致癫模型组TNF-α表达水平较对照组开始增高,AG490干预组TNF-α表达水平均较PILO致癫模型组明显降低(P<0.05);(3)PILO癫模型组可见阳性颗粒在星形胶质细胞内的空间分布,AG490腹腔注射建立干预后阳性颗粒的星形胶质细胞明显减少(P<0.05)。结论癫发作后TNF-α表达水平明显增高,提示星形胶质细胞增生。AG490可阻断JAK/STAT信号转导通路进而抑制星形胶质细胞活化,同时也可以影响癫大鼠的行为学变化,提示AG490对癫的发作可能有一定的抑制作用,其机制可能与其抑制星形胶质细胞增生有关。     

槲皮素对大鼠卵巢发育和卵巢寿命的影响

背景：研究发现一些植物雌激素可改变生殖系统发育,并可能最终影响生殖衰老的年龄。槲皮素是一种黄酮类物质,具有微弱的雌激素效应,但对卵巢卵泡发育和卵巢衰老进程究竟有无影响还不清楚。 目的：观察槲皮素对大鼠卵巢卵泡发育和卵巢寿命的影响。 方法：健康成年SD 大鼠30只雌雄按2∶1合笼所生的新生雌鼠,分为3组：母鼠灌胃组,对孕10.5 d母鼠槲皮素灌胃,1次/d,直至分娩,取1,2,4 d新生雌鼠;腹腔注射组,对正常出生后12 h内新生雌鼠槲皮素腹腔注射,1次/d,取2,4 d新生雌鼠;空白对照组：不进行任何干预的1,2,4 d新生雌鼠;观察新生鼠卵巢发育情况。另取12月龄雌性大鼠22只,以数字表法随机分为实验组和对照组：实验组用槲皮素灌胃4个月,1次/d;对照组灌胃给予生理盐水。对灌胃前和灌胃期间12月龄雌性大鼠行阴道涂片,观察大鼠动情周期模式;灌胃结束后,计算卵巢和子宫系数,苏木精-伊红染色观察各期卵泡发育情况和卵泡总数变化。 结果与结论：用槲皮素干预1,2 d龄新生大鼠未装配的卵泡均减少,而发育更晚期阶段的卵泡即原始卵泡或发育卵泡有所增加。灌胃前大部分大鼠动情周期已经不规则,用药后,随着大鼠年龄的增长,实验组与对照组显示了相似的动情周期变化：规则的动情逐渐消失,周期变得延长或不规则,灌胃结束时均以不规则动情为主。灌胃4个月后,实验组大鼠卵巢大部分由闭锁卵泡组成,另外可见少许原始卵泡、发育卵泡以及窦状卵泡和黄体,实验组窦状卵泡较对照组增加(P < 0.05),两组卵巢和子宫系数及体质量增加无差异。 提示槲皮素可能具有一定促进卵巢卵泡发育和成熟的作用,但不影响卵巢寿命。     

红藻氨酸诱导癫(癎)发作大鼠海马星形胶质细胞C-FOS基因表达的研究

目的研究癫发作大鼠海马星形胶细胞C-FOS基因表达的变化,探讨其对癫发作的维持与复发的影响。方法将83只成年雄性SD大鼠随机分为实验组58只,对照组25只。实验组在海马CA3区注射红藻氨酸(Kainicacid,KA)建立癫模型,对照组在相同部位注射等量生理盐水。利用免疫组织化学双重染色技术,分别在癫发作后1h、3h、6h、12h和24h观察大鼠海马星形胶质细胞C-FOS基因的表达。结果与对照组大鼠比较,癫模型鼠海马CA1区CFAP/C-FOS双标记阳性细胞百分率于癫发作后1h(12.70±0.03)、3h(17.10±0.05)、6h(24.92±0.04)明显升高(P<0.01),在6h达到高峰,在12h下降,但是仍较对照组高(10.71±0.06;1.59±0.02,P<0.01),在24h下降至对照组水平(2.00±0.02;2.08±0.03,P>0.05)。结论KA诱导大鼠癫发作,导致海马星形胶质细胞C-FOS基因相对持续的高表达,从而激活星形胶质细胞,产生高致性的病理环境,可能是癫发作的维持以及复发的病理生理机制之一。     

重组腺相关病毒神经肽Y基因转染对癫大鼠海马病理变化的影响

目的观察重组腺相关病毒介导人源性神经肽Y(rAAV-hNPY-EGFP)基因转染对癫大鼠海马病理变化的影响。方法 28只Wistar大鼠随机分为点燃组(n=20)和正常对照组(n=8)。正常对照组不进行特殊处理,点燃组以大鼠海马内多次注射红藻氨酸(KA)建立慢性癫模型,造模成功16只,其随机分为模型组和神经肽Y(NPY)治疗组,每组各8只大鼠。NPY治疗组大鼠转染rAAV2/1-hNPY-EGFP基因,模型组未转染。转染4周后,每组取6只大鼠海马行苏木精-伊红染色,2只行电镜观察。结果苏木精-伊红染色显示:正常对照组大鼠海马CA3区神经元形态正常;模型组海马CA3区神经元丢失,胶质细胞增生;NPY治疗组基因转染后神经元丢失减少。模型组神经元数目为(10.67±7.87)个/视野,正常对照组为(81.42±5.63)个/视野,明显多于模型组(P<0.05);而NPY治疗组神经元数目为(65.73±2.81)个/视野,明显多于模型组(P<0.05)。电镜显示:正常对照组神经元结构正常;模型组神经元固缩,线粒体肿胀;NPY治疗组神经元线粒体结构完整。结论 rAAV-hNPY-EGFP基因转染可减轻大鼠癫发作引起的病理改变,发挥抑制癫的作用。     

左乙拉西坦和托吡酯对癫(疒间)大鼠脑P-糖蛋白表达的影响

目的研究左乙拉西坦(LEV)和托吡酯(TPM)对癫大鼠脑P-糖蛋白(P-gp)表达的影响。方法将海人酸1.5μg(3μl)注射至SD大鼠海马制作癫模型(癫组),对照组大鼠海马注射3μl生理盐水(NS)。将癫组(18只)和对照组(15只)大鼠分别随机分为LEV、TPM和NS亚组(每亚组6只、5只),各亚组大鼠予相应药物(LEV50mg/kg、TPM40mg/kg、等体积NS)灌胃,每天1次,共30d。采用免疫组化EnVi-sion染色法检测大鼠颞叶、海马P-gp表达水平,采用LeicaQwin图像分析系统中平均整合灰度(MIB)值对P-gp表达水平进行半定量分析。结果癫各亚组大鼠颞叶和海马P-gp表达水平(MIB值)均显著高于其相应对照亚组(P<0.05～0.001);对照亚组中,LEV和TPM组与NS亚组间P-gp表达水平比较,差异无统计学意义;在癫组中,TPM亚组P-gp表达水平显著高于NS亚组(1550.3±371.9vs1049.7±282.8,P=0.004);而LEV亚组与NS亚组差异无统计学意义(1285.1±340.3vs1049.7±282.8,P=0.172)。结论癫发作可诱导...     

颞叶癫(癎)大鼠海马轴突导向分子Sema3F及其受体Np2表达的变化

目的研究颞叶癫大鼠海马轴突导向分子Sema3F及其受体Np2表达的变化。方法给SD大鼠腹腔注射匹罗卡品、氯化锂制作颞叶癫模型。用免疫组化法和原位杂交技术对致后不同时间点大鼠海马CA1区、CA3区、齿状回的Sema3F mRNA、Np2 mRNA和蛋白表达进行检测,并与正常对照组比较。结果颞叶癫大鼠致后7d、15d,海马CA1区、CA3区Sema3F mRNA、Np2 mRNA和蛋白的表达明显低于正常对照组(P<0.05~0.01),致后30d、60d表达与正常对照组差异无统计学意义;而齿状回Sema3F mRNA、Np2 mRNA和蛋白的表达与正常对照组的差异无统计学意义。结论颞叶癫大鼠海马CA1区、CA3区Se-ma3F、Np2表达在致后早期明显下调,而在慢性期恢复正常。     

幼鼠癫痫模型海马神经元NMDA受体表达与MMP-3表达相关性

目的 探讨幼鼠癫痫模型海马神经元N-甲基-D-天冬氨酸受体（NMDAR）表达与基质金属蛋白酶-3（MMP-3）表达的相关性。方法 将60只2~4周龄SPF级C57/BL6小鼠随机分为正常组、癫痫组、MMP-3抑制剂组、NMDAR抑制剂组,每组15只。采用匹罗卡品建立幼鼠癫痫模型;采用RT-PCR检测海马神经元NMDAR2A、NMDAR2B、MMP-3 mRNA表达;采用尼氏染色观察海马区神经元形态;采用Western blot检测海马区P-糖蛋白（P-gp）、钙调蛋白激酶Ⅱ（CAMKⅡ）蛋白表达。结果 幼鼠癫痫模型海马区NMDAR2A/B、MMP-3 mRNA以及P-gp、CAMKⅡ蛋白较正常组显著增加（P<0.05）。注射NMDA受体抑制剂或MMP-3抑制剂可显著降低幼鼠癫痫模型NMDAR2A/B、MMP-3 mRNA及P-gp、CAMKⅡ蛋白表达,且明显改善海马区神经元结构。结论 幼鼠癫痫模型海马神经元MMP-3表达与MNDAR表达可能具有相关性。     

葛根素对帕金森病保护作用的实验研究

目的 :探讨葛根素能否对雌激素水平降低的帕金森小鼠提供保护作用 ,为开发具有雌激素替代作用的药物预防和治疗 PD提供新的线索。方法 :采用免疫组化染色 (ABC法 )计数酪氨酸羟化酶 (TH)的阳性细胞数 ,TUNEL法观察每视野下凋亡细胞数目 ,比较各组的差异。结果 :正常雌性小鼠 MPTP造模组 (A组 )比去势后 MPTP造模组 (B组 )中给予生理盐水组 (B1组 )、 MPTP造模后去势组 (C组 )给予生理盐水组 (C1组 )的 TH阳性细胞数目明显增多 ,凋亡细胞数目减少 (P<0 .0 5 ) ;B组中给雌激素组 (B2组 )与给葛根素组 (B3组 )相比无显著性差异 (P>0 .0 5 ) ;B2组、 B3组与 B1组相比有显著性差异 (P<0 .0 5 ) ;B1组与 C1组相比无显著性差异 (P>0 .0 5 ) ;在 C组中 ,给雌激素组 (C2组 )和给葛根素组 (C3组 )比对照组 (C1组 ) TH阳性细胞数目增多 ,凋亡细胞数目减少 (P<0 .0 5 ) ,C2组与 C3组相比无显著性差异 (P>0 .0 5 )。结论 :葛根素对帕金森病具有保护作用 ,并与凋亡有关     

儿童癫的个性分析

目的　探讨儿童癫的个性特点。方法　采用艾森克人格问卷 (少年 )对 4 4例儿童原发性癫 (癫组 )及 4 0例健康儿童 (对照组 )进行对照研究。结果　癫组E量表分低于对照组 (P <0 .0 5 ) ,N、P、L量表均分高于对照组 ,经统计处理 ,差异有显著性 (P <0 .0 5 )。结论　患有癫疾病患儿个性偏于内向不稳定、精神质及对自己行为有掩饰现象。采用心理行为治疗、给予社会支持及精神支持可提高儿童癫的治疗质量。     

Effect of hormonal replacement therapy in the hippocampus of ovariectomized epileptic female rats using the pilocarpine experimental model

Amado and Cavalheiro [Amado, D., Cavalheiro, E.A., 1998. Hormonal and gestational parameters in female rats submitted to the pilocarpine model of epilepsy. Epilepsy Res. 32, 266-274], studying the establishment of the pilocarpine epilepsy model in female rats observed that the estrous cycle was dramatically altered during the three periods of this experimental model. This work was delineated to study the function of sexual hormones in the development of the epilepsy model induced by pilocarpine in ovariectomized rats. Experimental groups were: (a) control animals during estrus phase of the estrous cycle (E) and ovariectomized female rats (OVX) treated with saline instead of pilocarpine in the same volume, (b) experimental animals, that developed status epilepticus (SE) and were studied during the chronic phase of this model: intact chronic rats (CHRON) and ovariectomized chronic rats (OVX+CHRON) and (c) ovariectomized chronic rats, that were submitted to hormonal replacement therapy treated with: medroxyprogesterone (OVX+CHRON+MPA); 17beta-estradiol (OVX+CHRON+E2), or both (OVX+CHRON+E2+MPA). All ovariectomized animals showed genital atrophy 4 days after the surgical procedure. Moreover, all animals that developed SE and survived showed spontaneous recurrent seizures during the chronic phase. Concerning to seizure frequency, animals receiving medroxyprogesterone associated with 17beta-estradiol showed decreased seizures' number. However, animals that received only medroxyprogesterone therapy also showed reduction in the number of seizures. In addition, hormonal treatment was also able to stabilize the mossy fibers sprouting process, showing the importance of these hormones in the development of the epilepsy in female rats.     

硒元素对急性癫痫小鼠脑组织氧化损伤的影响

目的探讨微量元素硒对小鼠急性癫痫发作后脑组织氧化损伤的影响。方法将40只健康昆明小鼠按体重随机分为3组，即实验组、阳性对照组和阴性对照组。实验组小鼠经口灌胃Na2SeO2（20μg／kg），阳性对照组和阴性对照组小鼠给予0．9％氯化钠溶液，1次／d，连续7d；给药后第8天实验组和阳性对照组小鼠腹腔内注射青霉素600万U／kg，阴性对照组腹腔注射等体积0．9％氯化钠溶液，观察小鼠癫痫发生时的行为改变；小鼠被完全点燃后处死，比色法测定小鼠脑组织中谷胱甘肽过氧化物酶（GSH-Px）活性和丙二醛（MDA）含量。结果腹腔内注射青霉素后，实验组小鼠癫痫样发作出现时间较阳性对照组晚，且发作级别低。与阴性对照组相比，阳性对照组脑组织中GSH-Px活性显著下降（P〈0．01），MDA含量显著上升（P〈0．01）；与阳性对照组相比，实验组GSH-Px活性显著升高（P〈0．01），MDA含量显著下降（P〈0．01）。结论急性癫痫可引起脑组织氧化损伤，损害神经细胞。补硒可增加脑组织中GSH-Px活性，从而减轻氧自由基对机体造成的损害。     

Effect of bone marrow stromal cell transplantation to the hippocampal CA1 region on electroencephalographic activity in epileptic rats

BACKGROUND： Animal experiments have confirmed that bone marrow stromal cell （BMSC） transplantation can serve as a treatment for epilepsy. OBJECTIVE： BMSCs derived from green fluorescent protein （GFP） mice were transplanted into the hippocampal CA1 region of epileptic rats. The aim of the study was to record electroencephalogram （EEG）, analyze survival and migration of BMSCs, and validate the effect of BMSC transplantation for the treatment of epilepsy. DESIGN, TIME AND SETTING： A randomized block design experiment was performed at the Institute of Neuroscience, Kunming Medical College from March 2005 to February 2006. MATERIALS： Homozygous C57BL/6CrSlcTgN （acr-EGFP） OsbC 14-Y01-FM 131 mice, 8-12 weeks of age, were selected for preparation of cell suspension. Sprague Dawley rats were selected for establishing epilepsy models. METHODS： Rats were randomly divided into 4 groups： control （n = 8）, model （n = 8）, normal saline （n = 24）, and BMSC （n = 24）. In the model, normal saline, and BMSC groups, epilepsy was established with penicillin （3 × 10^7 U/kg i.p. ×7 days）. Rats in the BMSC group received a BMSC suspension derived from green fluorescent protein mice into the fight hippocampal CA1 region. Rats in the vehicle control group were injected with the same volume of normal saline into the hippocampal CA1 region. MAIN OUTCOME MEASURES： The electroencephalogram was used to monitor brain activity. Survival and migration of the transplanted BMSCs was observed using fluorescence microscopy at 1, 2, and 4 weeks after transplantation. RESULTS： In BMSC group, fluorescent cells were observed at the transplantation site and in the adjacent tissue, as well as in the tissue surrounding the needle tract, indicating the migration of implanted cells. Fluorescent cells were not detected in the vehicle control group. The electroencephalogram of the control animals exhibited 7-9 Hzα waves, with a wave amplitude 〈 50 μV. In the model and vehicle control groups random spike-and     

病灶切除辅以皮质癎灶热灼术治疗顽固性癫癎

目的　观察病灶切除辅以皮质灶横纤维热灼术治疗顽固性癫的临床效果。方法　将病灶切除辅以皮质灶热灼术 2 91例病人和单纯病灶切除术 78例病人的疗效进行分析比较。结果　病灶切除辅以皮质灶热灼组效果优于单纯病灶切除组 ,两者的临床效果存在显著性差异 (P <0 0 5 ) ;同时 ,病灶切除辅以皮质灶热灼术组无永久性的术后并发症。结论　病灶切除辅以皮质灶热灼术是治疗顽固性癫安全有效的方法 ,长期疗效有待进一步观察。     

Castration in female rats modifies the development of the pilocarpine model of epilepsy

Previous studies have shown that the susceptibility to pilocarpine-induced status epilepticus (SE) in female rats changes according to estrous cycle phases. These studies have also shown that following pilocarpine administration changes occur in gonadal, hypophyseal and hypothalamic hormones that could contribute for the sequence of the epileptic events. Accordingly, the present work aimed to investigate the role of sexual hormones withdrawal on the development of the pilocarpine model of epilepsy in female rats. With this purpose, castrated and non-castrated adult female Wistar rats were injected with pilocarpine and some characteristic parameters of the experimental model were observed. The results showed increased mortality after pilocarpine injection in the castrated rats when compared with non-castrated females. The latency period for SE onset and for the first spontaneous seizure was decreased in castrated when compared with non-castrated animals. The mossy fiber sprouting measured by neo-Timm scale during the chronic period, reached grade 3 for castrated epileptic rats while the non-castrated epileptic rats showed grade 2. Our results indicate that castration interferes with the epileptogenesis in the pilocarpine model of epilepsy suggesting that female sexual hormones could have protective effects against pilocarpine-induced SE.     

Significant effects of sex,strain, and anesthesia in the intrahippocampal kainate mouse model of mesial temporal lobe epilepsy

The intrahippocampal kainate mouse model of mesial temporal lobe epilepsy is increasingly being used for studies on epileptogenesis and antiepileptogenesis. Almost all previous studies used male mice for this purpose, and no study is available in this or other models of acquired epilepsy that directly compared epileptogenesis in female and male rodents. Epidemiological studies suggest that gender may affect susceptibility to epilepsy and its prognosis; therefore, one goal of this study was to investigate whether sex has an influence on latent period and epileptogenesis in the intrahippocampal kainate model in mice. Another aspect that was examined in the present study was whether mouse strain differences in epileptogenesis exist. Finally, we examined the effects of different types of anesthesia (chloral hydrate, isoflurane) on kainate-induced status epilepticus (SE) and epileptogenesis. Continuous (24/7) video-EEG monitoring was used during SE and the 2 weeks following SE as well as 4–6 weeks after SE. In male NMRI mice with chloral hydrate anesthesia during kainate injection, SE was followed by a seizure-free latent period of 10–14 days if hippocampal paroxysmal discharges (HPDs) recorded from the kainate focus were considered the onset of epilepsy. Anesthesia with isoflurane led to a more rapid onset and higher severity of SE, and not all male NMRI mice exhibited a seizure-free latent period. Female NMRI mice differed from male animals in the lack of any clear latent period, independently of anesthesia type. Furthermore, HPDs were only rarely observed. These problems were not resolved by decreasing the dose of kainate or using other strains (C57BL/6, FVB/N) of female mice. The present data are the first to demonstrate marked sex-related differences in the latent period following brain injury in a rodent model of acquired epilepsy. Furthermore, our data demonstrate that the choice of anesthestic agent during kainate administration affects SE severity and as a consequence, the latent period, which may explain some of the differences reported for this model in the literature.     

Catamenial‐like seizure exacerbation in mice with targeted ablation of extrasynaptic δGABA‐a receptors in the brain

Neurosteroids play a key role in catamenial epilepsy, a menstrual cycle‐related seizure clustering in women with epilepsy. While neurosteroids act on all GABA‐A receptor isoforms, they cause greater effects on extrasynaptic δGABA‐A receptors that mediate tonic inhibition in the brain. Previously, we identified a potential GABA‐A receptor mechanism for catamenial epilepsy. However, the precise functional role of extrasynaptic δGABA‐A receptors in the pathophysiology of catamenial epilepsy remains unclear. In this study, we utilized mice lacking extrasynaptic δGABA‐A receptors (δKO) to investigate whether reduction of tonic inhibition affects catamenial seizure susceptibility or intensity. Intact female wildtype (WT) and δKO mice were subjected to hippocampus kindling until they exhibited stage 5 seizures. Elevated gonadal hormone‐based neurosteroid levels were induced by standard gonadotropin regimen and neurosteroid withdrawal (NSW) was triggered by finasteride. NSW increased susceptibility to, as well the intensity of evoked catamenial‐like seizures in WT and δKO mice. However, fully kindled δKO mice exhibited an accelerated and augmented response to NSW, with a more rapid increase in seizure susceptibility and intensity than WT mice undergoing the NSW paradigm. Moreover, δKO mice in NSW showed reduced benzodiazepine sensitivity, but in stark contrast to the increased neurosteroid sensitivity observed in WT animals, δKO mice displayed no change in neurosteroid sensitivity in response to NSW. The increased catamenial seizure exacerbation and alterations in antiseizure drug responses are consistent with NSW‐induced changes in the abundance of δGABA‐A receptors. Collectively, these findings provide evidence of a potential protective role for extrasynaptic δGABA‐A receptors in catamenial‐like seizures. © 2017 Wiley Periodicals, Inc.