简介：BACKGROUND:Alpha-actinin(α-actinin)playsakeyroleinneuronalgrowthconemigrationduringdirectionaldifferentiationfromneuralstemcells(NSCs)toneurons.OBJECTIVE:Todetectinsitumicrodistributionandquantitativeexpressionofα-actininduringdirectionaldifferentiationofNSCstoneuronsinthetemporallobecerebralcortexofneonatalrats.DESIGN,TIMEANDSETTING:BetweenJanuary2006andDecember2008,cultureanddirectionaldifferentiationofNSCswereperformedatDepartmentofHistologyandEmbryology,PreclinicalMedicalCollege,ChinaMedicalUniversity.ImmuneelectronmicroscopywasperformedatDepartmentofHistologyandEmbryologyandDepartmentofElectronMicrology,PreclinicalMedicalCollege,ChinaMedicalUniversity.SpectrumanalysiswasperformedatLaboratoryofElectronMicroscopy,MentalResearchInstitute,ChineseAcademyofSciences.MATERIALS:Basicfibroblastgrowthfactor,epidermalgrowthfactor,brain-derivednervegrowthfactor,type-1insulinlikegrowthfactor,andα-actininantibodywereprovidedbyGibcoBRL,USA;rabbit-anti-ratnestinmonoclonalantibody,rabbit-anti-ratneuronspecificenolasepolyclonalantibody,andEDAX-9100energydispersiveX-rayanalysiswereprovidedbyPHILIPSCompany,Netherlands.METHODS:NSCs,followingprimaryandpassageculture,weredifferentiatedwithserumculturemedium(DMEM/F_(12)+10%fetalbovineserum+2ng/mLbrain-derivednervegrowthfactor+2ng/mLtype-1insulinlikegrowthfactor).MAINOUTCOMEMEASURES:Expressionofα-actinininneuron-likecellswasquantitativelyandqualitativelydetectedwithimmunocytochemistryusingenergydispersiveX-rayanalysis.RESULTS:Immunocytochemistry,combinedwithelectronmicroscopy,indicatedthatpositiveα-actininexpressionwaslikeaspheroidparticlewithhighelectrondensity.Inaddition,theexpressionwasgraduallyconcentratedfromthenuclearedgetothecytoplasmandexpandedintodevelopingneurites,duringdifferentiationofneuralstemcellstoneurons.Conversely,energydispersive