BasictissueCellswithintercellularmatrixEpithelialtissueConnectivetissueMuscletissueNervetissueChapter2EpitheliumZhengWei

DepartmentofHistologyandEmbryology,CMUClassificationofepi.Distributionoftheepi.Specializationoftheepi.MaincontentsCharacteristics(特點(diǎn))Distribution(分布)Classification(分類)Specialization(特殊結(jié)構(gòu))CharacteristicsNumerouscellswithlessintercellularmatrixPolarization:specializationsonfreeapicalsurface,lateralsurface,andbasalsurface.Avascularity(almost)RichinfreenervefiberterminalsClassificationofthecoveringepithelium單層上皮Simpleepi.單層扁平上皮Simplesquamousepi.單層立方上皮Simplecuboidalepi.單層柱狀上皮Simplecolumnarepi.假?gòu)?fù)層纖毛柱狀上皮Pseudostratifiedciliatedcolumnarepi.復(fù)層上皮Stratifiedepi.復(fù)層扁平上皮Stratifiedsquamousepi.復(fù)層立方上皮Stratifiedcuboidalepi.復(fù)層柱狀上皮Stratifiedcolumnarepi.變移上皮Transitionalepi.ClassificationofthecoveringepitheliumSimplesquamousepi.---內(nèi)皮endotheliumEndothelium:simplesquamousepitheliumliningtheinnersurfaceofheart,vessels,andlymphatics.LMofsectionofvessels(HE)Simplesquamousepi.---間皮mesothelumMesothelium:simplesquamousepitheliumcoveringthoracic,pericardial,andabdominalcavities.Stretchedpreparation(Silverstaining)Paraffinsectioning(HE)Simplesquamousepi.pulmonaryalveolus(HE)Parietallayerofrenalcorpuscle(HE)Simplecuboidalepi.Distribution:renaltubule,secretoryducts,ovariansurfaceSimplecolumnarepi.Distribution:lininginnersurfaceofStomach,intestine,anduterus.Pseudostratifiedsquamousepi.Distribution:mainlylininginnersurfaceofrespiratoryducts.Composition:ciliatedcolumnar,spindle,pyramid,gobletcells.Stratifiedsquamousepi.KeratinizedandnonkeratinizedstratifiedepitheliumStratifiedsquamousepi.---nonkeratinizedDistribution:coveringbodyasepidermisandlininginnersurfaceofesophagus,corneaouterepi.Transitionalepi.Definition:thenumberofcelllayersandcellshapeoftheepi.varywithenlargementandconstrictionoftheholloworganortubeDistribution:innersurfaceofurinaryducts.UrotheliumStratifiedcubicandcolumnarepi.GobletcellBasement

membraneciliaSpecializationofEpithelium游離面Freesurface側(cè)面Lateralsurface 基底面Basalsurface細(xì)胞衣cellcoat微絨毛Microvilli纖毛Cilia緊密連接Tightjunction中間連接Intermediatejunction橋粒Desmosome縫隙連接Gapjunction基膜Basementmembrane質(zhì)膜內(nèi)褶Plasmamembraneinfolding半橋粒HemidesmosomeJunctionalcomplex:morethan1junctionatsameplace.freesurfacelateralsurfacebasalsurfaceEpithelialspecializations

纖毛cilium

紋狀緣StriationborderMicrovilliandcilia(LM)Microvilliandcilia(TEM)MicrovilliCiliaMicrovilliandcilia(SEM)MicrovilliandciliaBothmicrovilliandciliaaredelicatefinger-likeprojectionsofapicalmembraneandcytoplasm（刷狀緣、紋狀緣inLM） Mv. CiliaLength: 1.4um(vary) 5-10umDiameter: 0.1um 0.2umEM:Core:microfilament microtubuleFunction: helpabsorption swing. Distribution:digestivesystem respiratorysys. renaltubules reproductivesys.Lateralspecializations(junctions)Fourtypesofcelljunctions

Tightjunction

OccludingjunctionZonulaoccludens

IntermediatejunctionAdhesivebeltsZonulaadherens

DesmosomeAdhesivespotMaculaeadherensgapjunctionCommunicatingjunctionMaculaecommunicatesTightjunctionIntermediatejunctionDesmosomeGapjunctionJunctionalcomplex:

morethan1junctionatsameplace.DesmosomeTightjunctionIntermediatejunctionBasalspecializationsEM：laminalucidabasallaminareticularlaminabasementmembraneLM：Plasmamembraneinfolding基膜BasementmembranePlasmainfoldingandbasementmembranebasementmembraneBasementmembranePASstainingBasementmembraneAsheet-likeextracellularstructureVisiblewithEMDenselayer,20-100nmthick,delicatenetworkoffinefibrils(laminadensa)Electronlucentlayersononeorbothsides.TypeIVcollagen,theglycoproteinslamininandentactin,andproteoglycan.Thecomponentsandthicknessofitvarywithinorbetweentissues.PASstaining(periodicacidandSchiff)內(nèi)分泌腺外分泌腺DevelopmentofglandGlandularepitheliumandglandGlandsareorganscomposedmainlyofglandularepithelia.Theepitheliaspecializedforsecretionaretermedglandularepithelia.ClassificationofGland:exocrineandendocrineExocrineglands:SecretoryunitesoracinusandductsShapeofthestructure:tubular,alveolarortubuloalveolar

Simplealveolar,simpletubularorcompoundtubulo-alveolar,etc.Classificationofexocrinegland

Serous,mucousormixedacinusAserousacinusiscomposedofseroussecretorycellsonly.Amucousacinusiscomposedofmucoussecretorycellsonly.Amixedacinusiscomposedoftheabovetwotypesofsecretorycells.Aserousglandismadeupofonlyseriousacinus,asparotidglandAmixedglandismadeupof3typesofaccinisuchasSubmandibularandsublingularglands.pancreasserousdemiluneExocrineglandserousacinimucousacinimixedaciniMixedglandmucousacinusSerousacinusSeroussecretorycell(acinus)LM:pyramid-shapewithabasally-placednucleus.Inapicalcytoplasm,eosinophiliczymogengranulesarepresent.EM:extensiverER;numerousmitochondria;Well-developedGolgicomplexFunction:Theacinusproducesaseroussecretion,whichisaclear,wateryfluidcontainingproteincomponents.M