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981.
目的观察D-半乳糖致衰老模型大鼠学习记忆能力和行为学情况,并探讨中药的干预作用。方法大鼠每日一次颈背部皮下注射5%D-半乳糖100 mg/kg。诱导大鼠衰老模型,连续7周,观察衰老模型大鼠的自主活动次数、空间记忆能力、主动回避遭受电击能力、探究活动等行为学表现和学习记忆能力,并用抗衰老片与首乌延寿片进行干预,观察中药的干预作用。结果皮下注射D-半乳糖造模后,衰老模型大鼠自主活动次数显著减少(P〈0.05,P〈0.01),水迷宫试验探索路径长度和搜台潜伏期显著延长(P〈0.05,P〈0.01),旷场试验移动路程长度和直立次数显著减少(P〈0.01),穿梭回避试验平均潜伏期、进入错误区时间显著增加(P〈0.05,P〈0.01)。给予抗衰老片与首乌延寿片干预后,衰老大鼠的自主活动次数显著增加(P〈0.01),水迷宫试验探索路径长度和搜台潜伏期显著缩短(P〈0.01),旷场试验移动路程长度和直立次数显著增加(P〈0.01),穿梭回避试验平均潜伏期、进入错误区时间显著减少(P〈0.05,P〈0.01)。结论D-半乳糖致衰老模型大鼠的自主活动次数减少,对新环境探索能力下降,学习记忆力下降;抗衰老片与首乌延寿片等中药可有效增强衰老模型大鼠的行为活动,提高衰老模型大鼠的学习记忆能力。 相似文献
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984.
Paromita Majumder Giulia Crispino Laura Rodriguez Catalin Dacian Ciubotaru Fabio Anselmi Valeria Piazza Mario Bortolozzi Fabio Mammano 《Purinergic signalling》2010,6(2):167-187
Connexin 26 (Cx26) and connexin 30 (Cx30) form hemichannels that release ATP from the endolymphatic surface of cochlear supporting
and epithelial cells and also form gap junction (GJ) channels that allow the concomitant intercellular diffusion of Ca2+ mobilizing second messengers. Released ATP in turn activates G-protein coupled P2Y2 and P2Y4 receptors, PLC-dependent generation of IP3, release of Ca2+ from intracellular stores, instigating the regenerative propagation of intercellular Ca2+ signals (ICS). The range of ICS propagation is sensitive to the concentration of extracellular divalent cations and activity
of ectonucleotidases. Here, the expression patterns of Cx26 and Cx30 were characterized in postnatal cochlear tissues obtained
from mice aged between P5 and P6. The expression gradient along the longitudinal axis of the cochlea, decreasing from the
basal to the apical cochlear turn (CT), was more pronounced in outer sulcus (OS) cells than in inner sulcus (IS) cells. GJ-mediated
dye coupling was maximal in OS cells of the basal CT, inhibited by the nonselective connexin channel blocker carbenoxolone
(CBX) and absent in hair cells. Photostimulating OS cells with caged inositol (3,4,5) tri-phosphate (IP3) resulted in transfer of ICS in the lateral direction, from OS cells to IS cells across the hair cell region (HCR) of medial
and basal CTs. ICS transfer in the opposite (medial) direction, from IS cells photostimulated with caged IP3 to OS cells, occurred mostly in the basal CT. In addition, OS cells displayed impressive rhythmic activity with oscillations
of cytosolic free Ca2+ concentration ([Ca2+]i) coordinated by the propagation of Ca2+ wavefronts sweeping repeatedly through the same tissue area along the coiling axis of the cochlea. Oscillations evoked by
uncaging IP3 or by applying ATP differed greatly, by as much as one order of magnitude, in frequency and waveform rise time. ICS evoked
by direct application of ATP propagated along convoluted cellular paths in the OS, which often branched and changed dynamically
over time. Potential implications of these findings are discussed in the context of developmental regulation and cochlear
pathophysiology. 相似文献
985.
不同地理来源头花蓼的遗传多样性与没食子酸含量相关性分析 总被引:1,自引:0,他引:1
应用ISSR-PCR和HPLC方法研究了头花蓼的遗传多样性与没食子酸之间的关系。ISSR结果显示居群总的遗传变异较大(Ht=0.2746),居群内的遗传变异较小(Hs=0.0804),居群间的遗传分化大于居群内的遗传分化。没食子酸含量经SPSS17.0分析显示,各居群间和居群内个体的没食子酸含量差异较大,居群间没食子酸含量范围在0.1738%~0.3306%,其中云南腾冲县,贵州台江县、纳雍县、余庆县、晴隆和毕节县居群间没食子酸含量差异均达到显著水平。通过对头花蓼48个地理居群的遗传多样性与没食子酸含量的相关分析,表明云南腾冲,贵州台江、毕节市亮岩镇、晴隆、盘县居群的遗传多样性指数、没食子酸含量较高,不仅可以作为人工育种的选育材料,而且对于头花蓼种植适生地区划研究具有很好的参考价值。 相似文献
986.
颈交感神经阻滞对严重烧伤大鼠肾脏的保护作用及其机制研究 总被引:1,自引:0,他引:1
目的:观察颈交感神经阻滞(CSB)对严重烧伤大鼠肾脏的保护作用,并对其可能机制进行初步探讨。方法:制作放烧严重烧伤伤大鼠大鼠模型,在伤后即刻及连续4天内进行双侧颈交感神经阻滞,观察生命体征、肾功能指标、肾脏组织学改变、血流灌注、抗氧化能力、肾组织Bcl-2表达改变。结果:经过颈交感神经阻滞处理后,伤后各时相点动物肾功能均较对照组为好,组织学病变减轻,器官血流量下降幅度减小,总抗氧化能力好于对照组,免疫组化显示CSB组肾组织中Bcl-2的表达较严重烧伤组明显增高。结论:颈交感神经阻滞可改善严重烧伤大鼠肾脏血液灌注,增强抗氧化能力,预防伤后肾脏功能损害。 相似文献
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Durk RC Singh K Cornelison CA Rai DK Matzek KB Leslie MD Schafer E Marchand B Adedeji A Michailidis E Dorst CA Moran J Pautler C Rodriguez LL McIntosh MA Rieder E Sarafianos SG 《PloS one》2010,5(12):e15049
Background
Foot-and-Mouth Disease Virus (FMDV) is a picornavirus that infects cloven-hoofed animals and leads to severe losses in livestock production. In the case of an FMD outbreak, emergency vaccination requires at least 7 days to trigger an effective immune response. There are currently no approved inhibitors for the treatment or prevention of FMDV infections.Methodology/Principal Findings
Using a luciferase-based assay we screened a library of compounds and identified seven novel inhibitors of 3Dpol, the RNA-dependent RNA polymerase of FMDV. The compounds inhibited specifically 3Dpol (IC50s from 2-17 µM) and not other viral or bacterial polymerases. Enzyme kinetic studies on the inhibition mechanism by compounds 5D9 and 7F8 showed that they are non-competitive inhibitors with respect to NTP and nucleic acid substrates. Molecular modeling and docking studies into the 3Dpol structure revealed an inhibitor binding pocket proximal to, but distinct from the 3Dpol catalytic site. Residues surrounding this pocket are conserved among all 60 FMDV subtypes. Site directed mutagenesis of two residues located at either side of the pocket caused distinct resistance to the compounds, demonstrating that they indeed bind at this site. Several compounds inhibited viral replication with 5D9 suppressing virus production in FMDV-infected cells with EC50 = 12 µM and EC90 = 20 µM).Significance
We identified several non-competitive inhibitors of FMDV 3Dpol that target a novel binding pocket, which can be used for future structure-based drug design studies. Such studies can lead to the discovery of even more potent antivirals that could provide alternative or supplementary options to contain future outbreaks of FMD. 相似文献989.