七氟醚对老龄大鼠海马CA3区突触结构的影响

目的观察七氟醚对老龄大鼠海马CA3区突触结构的影响。方法健康SD大鼠60只,18月龄,随机分为4组:空白对照组(C组)、3%七氟醚组(S1组)、1.5%七氟醚组(S2组)、3%异氟醚组(I组),每组15只。于麻醉结束后1、3、7 d(T1~T3)行Morris水迷宫实验,并测定海马CA3区突触结构各指标。结果与C组比较,I组T1~T3、S1组T1~T2时逃避潜伏期延长,穿越原平台象限次数减少,I组、S1组T1~T3海马CA3区突触间隙增宽,PSD厚度变薄,突触活性区长度缩短,突触界面曲率减小(P<0.05);与I组、S1组比较,S2组T1~T2时逃避潜伏期缩短,T1~T3海马CA3区突触间隙变窄,PSD厚度增厚,突触活性区长度延长,突触界面曲率增大(P<0.05);与I组比较,S1组、S2组T3时逃避潜伏期缩短,穿越原平台象限次数增加(P<0.05);与S1组比较,I组T3时逃避潜伏期延长,穿越原平台象限次数减少(P<0.05);与T1比较,I组、S1组、S2组T2~T3时逃避潜伏期缩短(P<0.05)。结论低浓度七氟醚对老龄大鼠认知功能无明显影响,高浓度七氟醚、异氟醚均可导致老龄大鼠认知功能减退,其机制可能与抑制海马CA3区突触结构的改变有关。     

硫化氢对老龄急性脑梗死大鼠认知功能的影响

目的评价硫化氢对老龄急性脑梗死大鼠认知功能的影响。方法选取健康雄性SD大鼠(青岛大学实验动物科学部提供)68只,月龄18²0个月,体重50020个月,体重500⁷00 g,采用随机数字表分为4组(n=17):对照组(C组)、模型组(M组)、Na HS组(N组)和生理盐水组(S组)。N组于制作模型前25 min给予大鼠腹腔注射H2S外源性供体Na HS(14μmol/kg);S组于制作模型前25 min给予大鼠腹腔注入等量的生理盐水;C组不行任何处理。采用线栓法致大鼠大脑中动脉阻塞致急性脑梗死模型。采用Morris水迷宫测试大鼠逃避潜伏期和穿越平台次数。采用ELISA法检测血清S-100β蛋白和NSE浓度。结果与C组比较,M组、N组和S组急性脑梗死后逃避潜伏期延长,穿越平台次数减少,T2、T3、T4各点血清S-100β及NSE浓度明显升高(P<0.05);与M组比较,N组急性脑梗死后逃避潜伏期缩短,穿越平台次数增多,T2、T3、T4各点血清S-100β及NSE浓度明显降低(P<0.05);与N组比较,S组急性脑梗死后逃避潜伏期延长,穿越平台次数减少,T2、T3、T4各点血清S-100β及NSE浓度明显升高(P<0.05),与第1天比较,M组、N组和S组各组第2700 g,采用随机数字表分为4组(n=17):对照组(C组)、模型组(M组)、Na HS组(N组)和生理盐水组(S组)。N组于制作模型前25 min给予大鼠腹腔注射H2S外源性供体Na HS(14μmol/kg);S组于制作模型前25 min给予大鼠腹腔注入等量的生理盐水;C组不行任何处理。采用线栓法致大鼠大脑中动脉阻塞致急性脑梗死模型。采用Morris水迷宫测试大鼠逃避潜伏期和穿越平台次数。采用ELISA法检测血清S-100β蛋白和NSE浓度。结果与C组比较,M组、N组和S组急性脑梗死后逃避潜伏期延长,穿越平台次数减少,T2、T3、T4各点血清S-100β及NSE浓度明显升高(P<0.05);与M组比较,N组急性脑梗死后逃避潜伏期缩短,穿越平台次数增多,T2、T3、T4各点血清S-100β及NSE浓度明显降低(P<0.05);与N组比较,S组急性脑梗死后逃避潜伏期延长,穿越平台次数减少,T2、T3、T4各点血清S-100β及NSE浓度明显升高(P<0.05),与第1天比较,M组、N组和S组各组第2⁵天逃避潜伏期缩短(P<0.05),与T1比较,M组、N组和S组T2、T3、T4各点血清S-100β及NSE浓度升高(P<0.05)。结论硫化氢可减轻急性脑梗死后大鼠认知功能障碍,其机制可能与降低血清S-100β和NSE浓度有关。     

铜对大鼠学习记忆和海马区超微结构的影响

目的观察铜负荷饮食对大鼠空间学习记忆行为和海马超微结构的影响。方法 40只雄性大鼠随机分为模型组和空白对照组各20只,采用Morris水迷宫实验测试大鼠学习记忆能力,采用原子吸收法检测肝、脑组织铜元素含量,电镜技术观察海马区超微结构变化。结果 Morris水迷宫实验:模型组大鼠在定位航行试验中平均逃避潜伏期较正常对照组显著延长,空间探索试验中穿越平台次数较正常组明显减少(P<0.01),与正常对照组比较,模型组大鼠肝、脑组织铜含量明显增加(P<0.01),海马组织内模型组大鼠神经元突触间隙明显变宽(P<0.05),突触后致密物厚度明显变薄(P<0.05)。结论铜可能通过损伤海马超微结构引起大鼠学习记忆功能障碍。     

戊四氮诱导癫痫大鼠的认知功能测定与海马超微结构观察

目的 探讨实验性癫痫持续状态(SE)对大鼠认知功能的影响及与大鼠海马CA1、CA3齿状回超微结构改变的关系.方法 30只大鼠随机分为SE组和对照组,戊四氮诱导大鼠SE,采用抬高迷宫和Mortis水迷宫试验观察大鼠情感反应和学习记忆功能的改变.电镜观察大鼠海马CA1、CA3区齿状回超微结构改变.结果 SE组大鼠在抬高迷宫开放臂中逃避时间延长(P＜0.01),进入次数增多(P＜0.01);水迷宫中逃避潜伏期延长(P＜0.01),搜寻策略改变(P＜0.05),平台象限游泳时间百分比降低(P＜0.01),穿越平台次数减少(P＜0.01).大鼠海马CA3区和齿状回分子层的神经元胞体固缩浓染,线粒体嵴局部消失,突起膜发生断裂,髓鞘板层松散,突触前后膜结构模糊,突触小泡减少,线粒体空化,星形胶质细胞高度水肿液化,核固缩.结论 SE使大鼠情感行为发生改变和学习记忆功能受损,可能与海马超微结构的改变有关.     

纳洛酮对脑震荡大鼠学习记忆和海马CA3区锥体细胞内钙离子的影响

目的：研究纳洛酮对大鼠脑震荡后空间学习记忆能力的影响及机制。方法：用金属单摆打击装置制作SD大鼠脑震荡模型,随机分为3组：假打击组,脑震荡组,脑震荡+纳洛酮组。用Morris水迷宫训练方法,评价动物的空间学习记忆能力,用激光共聚焦显微镜观察海马CA3区锥体细胞内钙离子荧光量值。结果：打击后d8～13脑震荡组隐匿平台逃避潜伏期明显比假打击组长(P＜0.01),穿越原平台位置水域的次数明显比假打击组减少(P＜0.01),海马CA3区锥体细胞内游离钙荧光量平均值(3.0±s 0.6)×10~6较假打击组(1.0±0.3)×10~6明显增高(P＜0.01)。脑震荡+纳洛酮组隐匿平台逃避潜伏期明显比脑震荡组缩短(P＜0.01),穿越原平台位置水域的次数明显比脑震荡组多(P＜0.01),海马CA3区锥体细胞内游离钙荧光量平均值(0.9±0.4)×10~6较脑震荡组明显减低(P＜0.01)。结论：纳洛酮能显著减轻大鼠脑震荡后的空间学习记忆障碍,其机制可能与其防止海马神经细胞内钙离子增高有关。     

七氟醚麻醉对子代大鼠海马神经元自噬的影响

目的探讨七氟醚麻醉对子代大鼠海马神经元自噬的影响。方法孕5~7 d的SD雌鼠18只,采用随机数字表法将其分为3组(n=6):对照组(C组)、七氟醚组(S组)、七氟醚+自噬抑制剂wortmannin组(SW组)。C组母鼠仅置于麻醉箱内,通入相同流量氧气暴露4 h,S组和SW组母鼠给予2.8%七氟醚吸入麻醉4 h。SW组子代大鼠于出生后1~3 d腹腔注射0.5 mg/kg自噬抑制剂wortmannin,C组和S组于相同时点腹腔注射等量的生理盐水对照。于出生后22 d,对各组子代大鼠进行水迷宫实验,测定其学习记忆功能,出生后28 d,完成水迷宫测试后处死子代大鼠,并取其海马组织。采用TUNEL染色测定子代大鼠海马组织内神经元的凋亡率,采用Western blot法检测子代大鼠海马组织内微管相关蛋白l轻链3(LC3)Ⅱ/LC3Ⅰ比值作为自噬活性的指标。结果 S组、C组子代大鼠逃避潜伏期较C组,穿越平台次数比较差异无统计学意义(P>0.05),SW组子代大鼠逃避潜伏期较C组延长,穿越平台次数较C组减少(P<0.05)。与C组比较,S组和SW组子代大鼠海马神经元的凋亡率和LC3Ⅱ/LC3Ⅰ比值均升高(P<0.05);与S组比较,SW组子代大鼠海马神经元的LC3Ⅱ/LC3Ⅰ比值降低(P<0.05)。结论大鼠孕期七氟醚麻醉对子代学习记忆功能无影响,其机制与激活生理性自噬对抗神经元凋亡有关。     

硫化氢对老龄急性脑梗死大鼠海马神经元腺苷酸活化蛋白激酶和星形胶质细胞的影响

目的评价硫化氢(H2S)对老龄急性脑梗死大鼠海马神经元腺苷酸活化蛋白激酶和星形胶质细胞的影响。方法健康雄性老龄SD大鼠96只,体重450⁵50 g,采用随机数字表法,将其随机分为4组:对照组(C组)、模型组(O组)、生理盐水+模型组(S组)、H2S组+模型组(H组),每组24只。采用线栓法致大鼠大脑中动脉阻塞致急性脑梗死模型。H组于制作模型前25 min给予大鼠腹腔注射H2S外源性供体NaHS(14μmol/kg);S组于制作模型前25 min给予大鼠腹腔注射注入等量的生理盐水;C组不行任何处理。采用Morris水迷宫法记录大鼠逃避潜伏期和游泳路径;采用RT-PCR法和Western-blot法分别测定大鼠海马AMPK mRNA和AMPK、p-AMPK的表达。采用免疫组织化学法计数GFAP阳性细胞总个数。结果与C组比较,O组、S组、H组大鼠逃避潜伏期和游泳路径延长,海马AMPK mRNA、AMPK、p-AMPK表达上调,GFAP表达细胞数量增多(P<0.05);与O组、S组比较,H组大鼠逃避潜伏期和游泳路径缩短,海马AMPK mRNA、AMPK、p-AMPK表达下调,GFAP表达细胞数量减少(P<0.05)。结论 H2S可改善老龄急性脑梗死大鼠认知功能,其机制可能与下调海马神经元腺苷酸活化蛋白激酶和抑制星形胶质细胞激活有关。     

头顶一颗珠提取物对D-gal所致大鼠脑衰老miR-155-3p的影响

目的探讨头顶一颗珠(TTM)对D-gal所致大鼠脑衰老miR-155-3p的影响。方法 50只SD大鼠分成5组,正常对照组,D-gal组, TTM组(低、中、高)。喂养6周后Morris水迷宫测试学习记忆能力后,处死大鼠,取海马,行HE和Nissl染色及8-OHdG免疫组织化学染色;q-PCR测定miR-155-3P;Western blot测Rheb、mTOR、p-mTOR和p70s6K。结果 Morris水迷宫测试D-gal组逃避潜伏期和路程长度均比正常组和TTM组长,穿越平台次数D-gal组少于正常组和TTM组(P<0.05)。D-gal组神经元排列不整齐,间隙增宽,TTM组好于D-gal组;正常组CA1区神经元尼氏小体颗粒较多,D-gal组明显减少,TTM组较模型组增多;8-OHdG与正常组相比,D-gal组明显升高(P<0.01),TTM组明显低于D-gal组(P<0.05);D-gal组海马miR-155-3P表达比正常组明显升高(P<0.05),TTM组miR-155-3P表达上调得到缓解(P<0.05);TTM上调D-gal海马组织中Rheb、p70S6K的表达,抑制mTOR。结论 D-gal所致大鼠海马中miR-155-3P表达增加,其可能机制是调控Rheb/mTOR/p70S6K通路,TTM能拮抗D-gal所致大鼠海马衰老。     

尼莫地平对弥漫性轴索损伤大鼠学习记忆改变及海马NF-κB蛋白表达的影响

目的研究尼莫地平(Nimodipine,NM)对弥漫性轴索损伤(Diffuse axonal injury,DAI)大鼠学习记忆改变及海马NF-κB蛋白表达的影响,探讨尼莫地平对DAI大鼠的脑保护机制。方法将36只大鼠随机分为正常对照组(NC组)、DAI组和NM组,每组12只,通过Morris水迷宫定位航行实验及空间探索实验,观察大鼠行为学改变,并用免疫组化和Western blot方法测定NF-κB蛋白的表达。结果 Morris水迷宫定位航行实验:与NC组比较,DAI组大鼠第1~3天逃避潜伏期明显延长(P<0.05);与DAI组比较,NM组大鼠第1~3天逃避潜伏期明显缩短(P<0.05)。空间探索实验:与NC组比较,DAI组大鼠2 min内穿越平台次数明显减少(P<0.05);与DAI组比较,NM组大鼠2 min内穿越平台区域的次数明显增加(P<0.05)。与NC组比较,大鼠DAI后NF-κB蛋白表达增加(P<0.05);与DAI组比较,NM干预后NF-κB蛋白表达明显降低(P<0.05)。结论 DAI大鼠学习记忆能力受损,主要表现为Morris水迷宫中逃避潜伏期延长,平台穿越次数减少。大鼠DAI后NF-κB蛋白表达增加,可能与轴索继发性损伤有关,NM可能通过抑制NF-κB蛋白的活化来实现其神经保护作用。     

噻吩诺啡对大鼠海马区突触可塑性的影响

目的考察噻吩诺啡慢性处理对大鼠海马区突触可塑性的影响,探讨药物对学习记忆(认知功能)的作用特点。方法大鼠噻吩诺啡慢性处理后,通过电生理学方法测定海马齿状回LTP的变化和免疫组化方法测定海马区学习记忆相关蛋白突触素含量的变化反映海马突触功能可塑性;通过电镜观察突触结构的超微变化并测定突触界面结构参数反映海马突触结构可塑性变化。结果①各药物慢性处理5 d,噻吩诺啡租大鼠在给予高频串刺激后,反映LTP现象的PS幅值显著增高至基线的(278±11)%,吗啡组大鼠为基线的(193±3)%,对照组为(152±6)%。②各处理大鼠在3 d,5 d海马脑区突触素的含量无明显变化;在8 d,与吗啡组比较,噻吩诺啡组大鼠海马突触素含量的明显升高(P<0.05),吗啡组大鼠海马突触素的含量与盐水对照组比较出现降低(P<0.05)。③各药物慢性处理14 d,噻吩诺啡组大鼠海马CA1区神经元胞核圆,核膜结构较清晰,极少数线粒体、内质网轻度扩张,肿胀;吗啡组大鼠海马CA1区神经元胞核大而圆,部分神经细胞核膜呈节段性结构不清楚,模糊,胞浆内线粒体及粗面内质网丰富,但有部分线粒体结构模糊,嵴消失,甚至空泡变性;盐水对照组大鼠海马CA1区结构正常。④各药物慢性处理14 d,与对照组相比,吗啡组、噻吩诺啡组三组大鼠突触活性区长度减小(P<0.05),吗啡组的PSD厚度明显减小(P<0.01);与吗啡组相比,噻吩诺啡组大鼠的PSD厚度增加及突触活性区长度增加(P<0.05),其他突触界面结构参数组间差异无显著性(P>0.05)。结论噻吩诺啡慢性处理对突触可塑性有影响,但其损害程度远小于吗啡,这可能是噻吩诺啡的低依赖性且区别于吗啡的突触机制之一。     

Interindividual variability in metabolic activation in humans in vivo

In assessing interindividual variability in metabolic activation, the toxic metabolite is often too unstable for conventional analysis. Possible alternatives include a stable product of the reactive metabolite e.g. cysteinyl derivatives of N-acetyl-4-benzoquinoneimine, the toxic metabolite of paracetamol, adducts with DNA or protein, and indirect measurement of the activity of the enzyme(s) producing the active metabolite. An example of the last approach is the use of furafylline, a highly specific inhibitor of human CYP1A2, to determine the extent of the metabolic activation of the cooked food mutagens PhIP and MeIQx. The extent of inhibition, determined from levels of unchanged amine in urine, is an indirect measure of the activity of the activation pathway. Further refinement of this approach, allied to improved measures of the biological process of interest should prove of value in evaluating interindividual variability and its role in the risk assessment process.     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg.kg) or i.p. (50 mg.kg) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) l.h. kg in the male rat and 10.6 (95% CI: 7.5, 15.0) l.h. kg in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p 0.001) in plasma obtained from the male (8.8 2.0%) compared with the female rat (11.7 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Theophylline kinetics in peripheral tissues in vivo in humans

Several biochemical and cellular effects have been described for methylxanthines under in vitro conditions. However, it is unknown, whether threshold concentrations required to exert these effects are attained in target tissues in vivo. We therefore employed the microdialysis technique for measuring theophylline concentrations in peripheral tissues under in vivo conditions.Following in vitro and in vivo calibration, microdialysis probes were inserted into the medial vastus muscle and into the periumbilical subcutaneous adipose layer of healthy volunteers. Following single oral dose administration of 300 mg or i.v. infusion of 240 mg theophylline, in vivo time courses of theophylline concentrations were monitored in tissues and plasma. Major pharmacokinetic parameters (c_max, t_max, AUC) were calculated for plasma and tissue time courses. The mean AUC_tissue /AUC_plasma-ratio was 0.56 (p.o.) and 0.55 (i.v.) for muscle and 0.55 (p.o.) and 0.72 (i.v.) for subcutaneous adipose tissue.We conclude that microdialysis provides important information on the distribution and the tissue pharmacokinetics of theophylline.Abbreviations FPIA Fluorescence polarisation immuno assay - AUC Area under the curve - t_max Time to peak concentration - c_max Peak concentration     

休克时血中氧自由基的变化

本实验测定10名休克患者血浆和红细胞的丙二醛(MDA)、血浆总抗的氧化活性(AOA)的含量。结果表明:休克病人红细胞膜和血浆 MDA 含量(4.298±0.722;5.348±0.834)与对照组(3.235±0.682;4.356±1.081)比较明显增高(P<0.05);血浆 AOA(39.65±7.858)与对照组(48.21±10.81)比较明显降低(P<0.01)。提示:休克时,患者机体内自由基反应增强是引起组织细胞损伤的原因之一。     

Polymorphisms in genes involved in neurotransmission in relation to smoking

Smoking behavior is influenced by both genetic and environmental factors. The genetic contribution to smoking behavior is at least as great as its contribution to alcoholism. Much progress has been achieved in genomic research related to cigarette-smoking within recent years. Linkage studies indicate that there are several loci linked to smoking, and candidate genes that are related to neurotransmission have been examined. Possible associated genes include cytochrome P450 subfamily polypeptide 6 (CYP2A6), dopamine D₁, D₂, and D₄ receptors, dopamine transporter, and serotonin transporter genes. There are other important candidate genes but studies evaluating the link with smoking have not been reported. These include genes encoding the dopamine D₃ and D₅ receptors, serotonin receptors, tyrosine hydroxylase, trytophan 2,3-dioxygenase, opioid receptors, and cannabinoid receptors. Since smoking-related factors are extremely complex, studies of diverse populations and of many aspects of smoking behavior including initiation, maintenance, cessation, relapse, and influence of environmental factors are needed to identify smoking-associated genes. We now review genetic polymorphisms reported to be involved in neurotransmission in relation to smoking.     

Tramadol concentrations in blood and in cerebrospinal fluid in a neonate

Based on blood and cerebrospinal fluid samples collected in a full-term neonate, the penetration of tramadol in the central nervous system is described. Following intravenous administration of tramadol, a lag time of about 4 h was observed until full blood–brain equilibration was achieved. This pharmacokinetic observation is in line with a recent pharmacodynamic evaluation of the central opioid effects of tramadol in adults.     

Disease control in asthmatic children seen in private practice in Switzerland

ABSTRACT

Background: Asthma is the most common chronic childhood disease in Switzerland with a prevalence of 10%. Asthma has a high economic burden accounting for high medical costs. Assessment of disease control is likely to be of help in the implementation of strategies to improve asthma. Therefore, we aimed to evaluate asthma control and therapy regimens among children in private practice.

Methods: We assessed asthma control as well as therapy regimens in 575 asthmatic children in an experience programme in Switzerland by using an abbreviated questionnaire based on the asthma control questionnaire and the child health questionnaire on Visit 1 and Visit 2.

Results: Good asthma control at Visit 1 was only present in 25.7% of asthmatic children. Occasional asthma symptoms, limitation of physical activity, nocturnal awakening and anxiety of the parent was present in 80.5%, 41.2%, 46.8% and 57% of the children, respectively. After adjustment of therapy regimens at Visit 1, mainly by adding a leukotriene receptor antagonist, asthma control was reported to be much better in 53.4% of the children at Visit 2.

Conclusions: As asthma control is inadequately achieved within a major portion of asthmatic children, it is imperative to find measures to improve asthma control and hence, to reduce the burden of disease.