NMDA受体NR1亚单位与GABA_A受体在精神分裂症小鼠海马齿状回颗粒细胞层的表达

目的:明确NMDA受体NR1亚单位、GABAA受体与精神分裂症(SP)小鼠海马齿状回颗粒细胞层新生颗粒细胞的共存模式;阐明NR1、GABAA受体在SP小鼠海马中的表达。方法:实验组小鼠腹腔注射MK-801(每日0.6 mg/kg),对照组注射等量的生理盐水,连续注射14 d后对两组动物分别进行BrdU标记,断头并进行如下处理:(1)免疫荧光染色,观察海马DG区中NR1和GABAA的表达以及与BrdU标记的新生颗粒细胞的共存模式;(2)利用RT-PCR技术,检测海马GABAA及NR1 mRNA表达水平的改变。结果:(1)停药后实验组与对照组比较,海马神经细胞的增殖率下降了23.1%(P0.05),GABAA、NR1两种神经细胞增殖数无差异性改变(P0.05);(2)实验组小鼠海马GABAAmRNA的表达量较对照组显著下降(P0.05),而NR1 mRNA的表达量较对照组明显增高(P0.05)。结论:(1)小鼠精神分裂症后可引起海马齿状回神经细胞增殖的降低;(2)小鼠精神分裂症后,在mRNA水平上,海马GABAA的表达降低,NR1的表达升高。     

侧脑室注射NMDA对精神分裂症小鼠海马颗粒细胞层NMDA受体NR1亚基表达的调控

目的:阐明N-甲基-D-天冬氨酸受体亚单位1(NR1)在精神分裂症小鼠海马CA1、CA3、DG区颗粒细胞层的表达及NMDA对其表达的调控作用。方法:将小鼠随机分为实验组、对照组及空白组,实验组每日连续腹腔注射MK-801(0.6 mg/kg)14 d后侧脑室注射NMDA 1次,72 h后取材,应用免疫荧光标记法检测各组小鼠海马CA1、CA3、DG区颗粒细胞层NR1阳性细胞的表达。结果:对照组小鼠DG区NR1阳性细胞的表达比实验组和空白组明显升高(P0.05);在CA1区,实验组NR1的表达与对照组及空白组相比显著降低(P0.05);在CA3区,对照组NR1的表达与空白组相比显著降低(P0.05)。结论:(1)精神分裂症小鼠海马颗粒细胞层NR1阳性细胞的表达在DG区和CA1区显著升高,CA3区显著降低;(2)NMDA可调节精神分裂症小鼠海马结构颗粒细胞层NR1阳性细胞的表达趋于正常水平。     

NF-KB在发育鼠戊四氮反复点燃癫痫形成中的作用

目的:用NF-KB阻滞剂吡咯烷二硫基甲酸盐(PDTC)阻断NF-KB的表达,探讨核因子KB(NF-KB)在发育鼠戊四氮(PTZ)点燃癫痫形成过程中的作用.方法:生后10 d(P10)Wistar大鼠72只,随机分为PTZ组、PDTC PTZ组及生理盐水对照组3组,制备戊四氮反复点燃癫痫模型.观察各组大鼠行为学改变、海马各区细胞形态及细胞计数、NF-KB表达、5-溴-2-脱氧尿嘧啶核苷(BrdU)阳性细胞数和苔藓纤维发芽等指标.结果:(1)NF-KB表达,PTZ组显著高于对照组及PDTC PTZ组(P<0.01);(2)海马神经细胞计数,PTZ组齿状回(DG)区颗粒细胞较对照组显著增加(P<0.05);PDTC PrZ组CAI、CA3和门区神经元数较PTZ组均明显减少(P(0.05);(3)DG区BrdU阳性细胞数,PTZ组和PDTC PTZ组均较对照组显著增加(P<0.01);PDTC PTZ组DG区BrdU阳性细胞数目明显较PTz组少(P<0.01);NF-KB吸光度值与BrdU阳性细胞数／颗粒细胞数相关性分析呈正相关,具有统计学意义(P<0.01);(4)苔藓纤维发芽,PDTC PTz组和PTZ组均有苔藓纤维发芽,两组比较没有显著差异.结论:NF-KB在发育鼠癫痫中发挥重要作用,促进海马神经元发生,保护海马神经细胞,但对苔藓纤维发芽无明显作用.     

NF-κB在发育鼠戊四氮反复点燃癫痫形成中的作用

目的：用NF-κB阻滞剂吡咯烷二硫基甲酸盐(PDTC)阻断NF-κB的表达，探讨核因子κB(NF-κB)在发育鼠戊四氮(PTZ)点燃癫痫形成过程中的作用。方法:生后10 d（P10）Wistar大鼠72只，随机分为PTZ组、PDTC＋PTZ组及生理盐水对照组3组，制备戊四氮反复点燃癫痫模型。观察各组大鼠行为学改变、海马各区细胞形态及细胞计数、NF-κB表达、5-溴-2-脱氧尿嘧啶核苷(BrdU)阳性细胞数和苔藓纤维发芽等指标。结果:(1)NF-κB表达，PTZ组显著高于对照组及PDTC+PTZ组（P<0.01）；(2)海马神经细胞计数，PTZ组齿状回（DG）区颗粒细胞较对照组显著增加(P<0.05)；PDTC+PTZ组CA1、CA3和门区神经元数较PTZ组均明显减少（P<0.05）；(3)DG区BrdU阳性细胞数，PTZ组和PDTC+PTZ组均较对照组显著增加（P<0.01）；PDTC＋PTZ组DG区BrdU阳性细胞数目明显较PTZ组少（P<0.01）；NF-κB吸光度值与BrdU阳性细胞数/颗粒细胞数相关性分析呈正相关，具有统计学意义（P<0.01）；（4）苔藓纤维发芽，PDTC＋PTZ组和PTZ组均有苔藓纤维发芽，两组比较没有显著差异。结论:NF-κB在发育鼠癫痫中发挥重要作用，促进海马神经元发生，保护海马神经细胞，但对苔藓纤维发芽无明显作用。     

大鼠侧脑室注射GABA对束缚-浸水应激性胃溃疡的影响

为探索脑内γ-氨基丁酸(GABA)对应激性胃溃疡的影响及其机制,采用大鼠束缚-浸水应激性胃溃疡模型,观察了侧脑室注射γ-氨基丁酸及其A型受体的激动剂和拮抗剂对大鼠应激性胃溃疡的影响。结果表明:与侧脑室注射生理盐水组比较:(1)侧脑室注射γ-氨基丁酸,大鼠束缚-浸水应激性胃溃疡程度显著减轻(P<0.01);(2)侧脑室注射戊巴比妥钠(GABAA型受体激动剂),胃溃疡程度也显著减轻(P<0.05);(3)侧脑室注射荷包牡丹碱(GABAA型受体拮抗剂),胃溃疡程度明显加重(P<0.05)。这些结果表明:外源性γ-氨基丁酸对大鼠束缚-浸水应激性胃溃疡的形成有抑制作用,这种抑制作用是通过脑内GABAA型受体介导的;在应激过程中,脑内也有内源性γ-氨基丁酸的释放并通过其A型受体的活动,减轻胃溃疡的形成。     

癫痫发作后成鼠及幼鼠海马神经发生的改变

目的:观察幼鼠及成鼠癫痫发作后海马神经发生的变化。方法:选用3周龄和成年雄性SD大鼠,氯化锂-匹罗卡品药物点燃造模,造模成功后根据溴脱氧尿嘧啶核苷(BrdU)注射时间点分为24 h组、2周组,并设相应的对照组。通过免疫荧光染色技术在激光共聚焦显微镜下观察幼鼠及成年鼠海马齿状回颗粒细胞层神经细胞的增殖情况。结果:(1)幼鼠24 h及2周实验组海马齿状回颗粒细胞层BrdU阳性细胞数均显著高于相应对照组(P<0.05),且24 h组较2周组显著增多(P<0.05);(2)成年鼠24 h实验组的BrdU阳性细胞数明显多于相应对照组(P<0.05),而2周组则相反(P<0.05)。结论:癫痫发作可导致海马神经发生的改变,幼鼠癫痫发作后海马齿状回颗粒细胞层神经细胞增殖显著升高,但随着时间延长呈下降趋势。慢性癫痫发作可引起成年鼠海马神经细胞增殖的降低。     

缺血再灌注损伤对成年大鼠脑室下区神经干细胞增殖和NMDA受体亚单位2A表达的影响

目的:研究缺血再灌注损伤对成年大鼠脑室下区(SVZ)神经干细胞增殖和NMDA受体亚单位NR2A表达的影响,探讨NR2A在神经干细胞增殖中的作用。方法:正常成年雄性SD大鼠45只,随机分成正常组、假手术组和缺血再灌注组,线栓法制作大脑中动脉栓塞(middle cerebral artery occlusion,MCAO)2 h再灌注模型,术后分3、7、14 d三个时间点取脑。行免疫组织化学染色观察Nestin、增殖细胞核抗原(PCNA)及NMDA受体亚单位NR2A阳性细胞数。结果:(1)各组大鼠SVZ均可见Nestin和PCNA阳性细胞,缺血再灌注后3 d,脑室下区Nestin IOD值和PCNA阳性细胞增加(P0.05),7 d达到高峰(P0.05),14 d后有所下降(P0.05)。(2)各组大鼠SVZ均表达NR2A阳性细胞,缺血再灌注后3 d,NR2A阳性细胞数开始增加(P0.05),7 d也达到高峰(P0.05),14 d阳性细胞数有所下降,但维持较高的水平(P0.05)。(3)缺血再灌注后不同时间点NR2A阳性细胞数与PCNA阳性细胞数有高度正相关性(r=0.985,P0.05)。结论:缺血再灌注损伤能刺激成年大鼠SVZ神经干细胞的增殖;缺血再灌注后NMDA受体亚单位NR2A表达增加,并且与神经干细胞的表达变化趋于一致,因此推断NR2A可能参与缺血再灌注大鼠SVZ神经干细胞的增殖过程。     

癫痫大鼠海马NMDA受体亚基NR2A和BDNF mRNA水平的检测

目的 通过锂-匹罗卡品癫痫模型(ithium-pilocarpine seizures rats model of epilepsy,LPS),研究NMDA受体亚基NR2A、BDNF mRNA的表达,探讨NR2A、BDNF在LPS中的作用.方法 建立氯化锂-匹罗卡品大鼠模型,运用原位杂交技术检测致痫后各组不同时间点海马CA1、CA3及DG区NR2A与BDNF mRNA的表达.结果 LPS海马NR2A、BDNF mRNA在各观察时间点及部位模型组与正常对照组比较均有明显上调,且有显著统计学差异(P＜0.05).模型组NR2A mRNA的表达上调7 d达峰值(P＜0.05);而BDNF mRNA表达上调14 d达峰值.VPA干预组NR2A mRNA在大鼠海马不同时间及部位(除1 d的CA3区)的表达较模型组明显下调(P＜0.05);BDNF mRNA在大鼠海马不同时间及部位(除28 d的DG区)的表达较模型组明显下调(P＜0.05).结论 锂-匹罗卡品腹腔注射可诱导大鼠海马NR2A和BDNF mRNA的表达明显上调;NR2A mRNA表达的增强可能是诱导调控BDNF mRNA表达增强的重要机制之一,说明NMDA受体亚基NR2A可能成为抑制癫痫发作的新靶点.     

青春期大鼠癫痫发作后海马齿状回颗粒细胞层神经细胞增殖的改变

目的:探讨青春期大鼠癫痫发作后海马齿状回颗粒细胞层神经细胞数量的变化。方法:选择健康4周龄雄性SD大鼠,应用氯化锂-匹罗卡品药物点燃造模,造模成功后根据取脑组织时间分为24 h组、2周组、4周组,并设相应的对照组。溴脱氧尿嘧啶核苷(BrdU)标记后免疫荧光染色,用激光共聚焦观察大鼠海马齿状回(DG)颗粒细胞层BrdU阳性细胞。结果:24 h和2周实验组BrdU阳性细胞显著增多,分别较对照组增加55.1%和39.6%,2周实验组比24 h实验组降低15.5%(P<0.05);4周实验组BrdU阳性细胞数较对照组无明显差异(P>0.05)。结论:青春期大鼠癫痫发作可引起海马齿状回颗粒层神经细胞增殖的升高,但随着时间的延长有下降的趋势,至4周左右神经细胞的增殖趋于正常。     

NMDA受体在正常大鼠颈动脉体的表达

应用免疫组织化学方法观察了离子型谷氨酸受体——NMDA受体的NR1及NR2A亚单位在正常成年雄性SD和Wistar大鼠颈动脉体的表达,并对阳性产物的表达强度进行了灰度分析及统计学处理。结果表明:正常成年SD大鼠及Wistar大鼠的颈动脉体内均存在NMDA NR1免疫反应阳性细胞,从阳性细胞的形态和分布特点判断这些阳性细胞为主细胞,两种大鼠之间无明显差异(P>0.05);而两种大鼠的颈动脉体内几乎不存在NMDA NR2A免疫反应阳性细胞。本实验的结果提示:在正常成年大鼠颈动脉体的主细胞上有NMDA受体的分布,并且该受体的二聚体构成不同于经典受体,这可能与谷氨酸在颈动脉体发挥的特殊功能有关。     

雷公藤甲素抗肿瘤血管新生的研究进展（英文）

雷公藤甲素(triptolide,TPL)是从中草药雷公藤中提取的一种有效活性物质,已被用来治疗多种疾病,包括系统性红斑狼疮,类风湿性关节炎,肾病综合征等,TPL甚至有很强的抑制肿瘤的活性。近些年的研究显示,TPL具有抗血管新生的能力,TPL不仅可以抑制肿瘤的增殖,诱导细胞的凋亡,还可以抑制肿瘤的转移,可以增加其它化疗药物的抗肿瘤活性。本综述将讨论TPL在抗肿瘤血管新生方面的研究进展,以及初步探讨其潜在的作用机制。     

Restoration of in vitro responses in platelets stored in plasma

Conventional platelet storage in a blood bank is up to 5 days at room temperature in plasma. We investigated the optimal medium for assessing the quality of stored platelets by comparing in vitro test responses after resuspension in autologous plasma prepared from platelet-rich plasma after 5 days of storage at room temperature, autologous plasma stored cell-free for 5 days at room temperature, or autologous plasma stored cell-free for 5 days at -20 degrees C. Five-day-old platelets were prepared from aliquots of the same unit and resuspended in I of the 3 plasma preparations. The platelet-plasma mixtures were monitored for changes in pH, mean platelet volume, hypotonic shock response, P-selection expression, and aggregation. There were statistically significant differences between platelets resuspended in original plasma and platelets resuspended in either plasma stored cell-free at room temperature or frozen, with regard to hypotonic shock response, agonist-induced aggregation, and P-selectin expression. Plasma stored with platelets for 5 days yielded inferior platelet function test responses when compared with plasma stored cell-free at room temperature or frozen. Therefore, for direct comparison of platelet responses following novel storage methods, the resuspending plasma should be stored under the same conditions as the control platelet unit.     

Changes in activity of neutral proteases in tissues of ground squirrels in the dynamics of hibernation

Total activities of neutral proteases in the cerebral, hepatic, and myocardial tissues of ground squirrel vary during hibernation: in autumn (before hibernation) activities of the enzymes in the brain and myocardium start increasing, while in the liver they do not change. A common feature for all tissues is minimum activity of active neutral proteases in the middle of hibernation month 1 bout, while the maximum activity is recorded before awakening. Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 9, pp. 278–280, September, 2008     

Kinetics of decline of maternal measles virus-neutralizing antibodies in sera of infants in France in 2006

The optimal age for measles vaccination is an important health issue, since maternal antibodies may neutralize the vaccine antigen before a specific immune response develops, while delaying vaccination may increase the risk of complicated diseases in infants. However, measles vaccination impacts the duration of protection afforded by transplacental transfer of maternal antibodies: vaccination-induced maternal antibodies disappear faster than disease-induced antibodies. In order to maintain protection against measles in infants, it is important to monitor the dynamics of this phenomenon in vaccinated populations. To assess the current situation in France, a multicenter, prospective seroepidemiological study was conducted in seven French hospitals between October 2005 and January 2007. Maternal measles antibody concentrations from 348 infants 0 to 15 months old were measured using the plaque reduction neutralization assay. Geometric mean concentrations and the percentage of infants with maternal measles antibody concentrations above the protection threshold (≥120 mIU/ml) were assessed according to age. Results show that after more than 20 years of routine measles vaccination in France, maternal measles-neutralizing antibodies decrease dramatically in French infants by 6 months of age, from 1,740 mIU/ml for infants 0 to 1 month old to 223 mIU/ml for infants 5 to 6 months old, and that 90% of infants are not protected against measles after 6 months of age. Infant protection against measles could be optimized both by increasing herd immunity through an increased vaccine coverage and by lowering the age of routine vaccination from 12 to 9 months.