Glycine uptake regulates hippocampal network activity via glycine receptor-mediated tonic inhibition

Functional glycine receptors (GlyRs) are enriched in the hippocampus, but their role in hippocampal function remains unclear. Since the concentration of ambient glycine is determined by the presence of powerful glycine transporter (GlyT), we blocked the r

云南基诺族及汉族特发性全面强直-阵挛性癫(癎)与CLCN2基因的相关性

目的 研究氯离子通道CLC-2基因是否与中国云南地区基诺族及汉族特发性全面强直-阵挛性癫(癎)(IGTCS)相关.方法 以14例云南西双版纳傣族自治州景洪市基诺乡基诺族IGTCS患者及其16名未发病亲属、67例云南籍汉族IGTCS患者及57名云南籍汉族健康体检者为对照,对常染色体3q26上CLCN2基因的内含子2及外显子5、19(内含子18)进行研究,采用PCR及直接基因测序技术,应用病例-对照研究法对CLCN2基因与云南基诺族及汉族IGTCS进行相关性分析.结果 CLCN2基因的内含子2及外显子5、19在病例组和对照组中均没有发现已报道的易患突变,但我们在对外显子19的序列测定过程中发现了其上游内含子18的146位上存在1个单核苷酸多态性位点:146T→C.该位点的3种基因型(TT、TC、CC)在汉族病例组(9、3、29例)和汉族对照组(22、9、26例)之间的分布差异有统计学意义(x2=16.079,P＜0.05);在基诺族组(基诺族病例组+基诺族亲属组,6、12、12例)与汉族对照组(22、9、26例)之间分布差异亦有统计学意义(x2=7.027,P＜0.05).汉族病例组与汉族对照组间TT型与非TT型基因型(分别为9、32例和22、35例)、TC型与非TC型基因型(分别为3、38例和9、48例)比较差异有统计学意义(x2=10.694,OR=4.121,P＜0.05;x2=11.592,OR=0.238,P＜0.05).结论 CLCN2基因内含子18的多态性位点146T→C可能是中国云南地区基诺族与汉族IGTCS患者的1个相关性位点,且在本组有限的样本数量研究中,此SNP位点在两个民族IGTCS患者之间的分布无民族差异.基因型TT为IGTCS的1个保护性因素,基因型TC则增加了患者的易患性.

Stress within the postseizure time window inhibits seizure recurrence

Recurrence is a key characteristic in the development of epilepsy. It remains unclear whether seizure recurrence is sensitive to postseizure stress. Here, tonic-clonic seizures were induced with a convulsive dose of pentylenetetrazole (PTZ), and acute seizure recurrence was evoked with a subconvulsive dose of the drug. We found that stress inhibited seizure recurrence when applied 30 minutes or 2 hours, but not 4 hours, after the tonic-clonic seizure. The time-dependent anti-recurrence effect of stress was mimicked by the stress hormone corticosterone and blocked by co-administration of mineralocorticoid and glucocorticoid receptor antagonists. Furthermore, in a PTZ-induced epileptic kindling model, corticosterone administered 30 minutes after each seizure decreased the extent of seizures both during the kindling establishment and in the following challenge test. These results provide novel insights into both the mechanisms of and therapeutic strategies for epilepsy. (C) 2010 Elsevier Inc. All rights reserved.

Separation and determination of organogermanium compounds by ion chromatography

For nearly three decades, organogermanium compounds have become increasingly of interest owing to their extensive physiological and pharmaceutical activity. In this paper, two new high performance ion chromatographic methods for separation and determination of three kinds of organogermanium compounds beta-carboxyethylgermanium sesquioxide (I), beta-(alpha-methyl)-carboxyethylgermanium sesquioxide (II) and d-(beta-carboxyethyl)germanium hydroxide (III) were proposed. A Dionex DX-300 ion chromatograph equipped with a Dionex FED-II pulsed electrochemical detector (conductivity mode), and a Dionex AI-450 chromatography workstation was employed. The separation was achieved by using ion-exchange or ion-exclusion mechanism. The detection limits(S/N=3, expressed as germanium) for the three compounds were all below sub- mu g/mL level. The methods have been applied to the analysis of tonic oral drinks, and the average recoveries for the three compounds range from 95 - 108%. The results obtained were in agreement with those of hydride generation atomic fluorescence spectrometry (HG-AFS).