apoe41272过表达触发ers损伤大鼠空间记忆能力word格式论文.docxVIP

中文摘要目的apoE4等位基因是公认的迟发型AD的危险因素之一，国内外研究提示其截断型片段apoE4(1-272)可能在AD发病过程中发挥重要作用，但机制不清。本研究探讨apoE4(1-272)是否可通过诱发内质网应激（endoplasmic reticulumstress,ERS）进而损伤大鼠空间参考记忆能力。方法将SD大鼠分为两组，假手术组和apoE4（1-272）转染组，48h后荧光显微镜检测海马区的荧光表达。24 只SD雄性大鼠，随机分为四组：对照组，pEGFP转染组，apoE4(1-272)转染组和4-PBA处理组。4-PBA处理组先采用4-PBA（1g/kg/天）灌胃大鼠12周，然后采用脑立体定位注射将pEGFP-apoE4(1-272)基因转染至大鼠双侧海马区，继续每日4-PBA灌胃。各组大鼠术后48-72 小时取双侧海马组织，一侧组织冰冻切片行荧光显微镜检测，一侧组织留做Westernblot检测ApoE4(1-272)和ERS标志蛋白GRP78 的表达。转染后一周Morris 水迷宫检测大鼠的空间参考记忆。结果荧光显微镜及Westernblot检测表明apoE4(1-272)质粒可通过定位注射到大鼠海马区并有效表达。Westernblot结果显示ApoE4(1-272)过表达可诱导大鼠海马组织GRP78的表达量增加，4-PBA处理组可有效抑制该效应（P0.01）。Morris水迷宫检测显示：ApoE4(1-272)过表达可导致大鼠空间记忆损伤，与对照组和pEGFP转染组相比，差异具显著性（P0.01）；4-PBA处理组可显著减轻ApoE4(1-272)过表达所致的大鼠空间记忆损伤，差异具显著性（P0.01）。结论ApoE4(1-272)过表达可触发大鼠海马组织内质网应激进而导致大鼠空间记忆损伤。关键词阿尔茨海默病apoE4(1-272)内质网应激GRP784-PBAABSTRACTAimHumanapolipoprotein(apo)E4isoneofproverbialmajorriskfactorsfor Alzheimers disease (AD).Studies suggestedthat truncated-apoE4fragments apoE4(1-272)takepart in the pathology processof AD. However, the mechanismof increasingthe risk of ADanditsroleinthepathogenesisofADarenotfullyunderstood.WeinvestigatewhetherapoE4(1-272)inducesthespatial memoryimpairmentofratsbytriggeringtheendoplasmicreticulumstress(ERS)inrathippocampus.MethodsSDratsweredividedintotwogroups,shamgroup,apoE4(1-272)transfectiongroup.At48hoursaftertransfection,fluorescencemicroscopedetectedtheflorescence.24maleSDratswererandomlydividedintofourgroups,controlgroup, pEGFPtransfectiongroup,apoE4(1-272)transfectiongroupand4-PBAtreatmentgroup. Theratsof4-PBAgrouphavebeeninjected4-PBA(1g/kg/day)byusingthestomachtubefor12weeksbeforeapoE4(1-272)transfectiontothehippocampusbystereotaxisinstrument,thencontinuetobelavaged.At48-72hoursaftertransfection,therat’shippocampuswereharvestedforanalysesoftheexpressionofApoE4(1-272)andERSmarkerGRP78byfluorescencemicroscopyandWesternblot.Atoneweekaftertransfection,Morriswatermazewasusedtotestthespatialreferencememoryoftheserats.ResultsTheresultsoffluorescencemicroscopyandWeste