1、 组织胚胎学课件组织胚胎学课件 七年制英文医学班专用七年制英文医学班专用中国医科大学中国医科大学基础医学院基础医学院组胚组胚英文教学组英文教学组 Chapter 3 Connective tissue1.Generalfeatures:1)smallnumberofcellsandlargeamountofextracellulargroundsubstance2)extracellular is composed of fibers andamorphousgroundsubstance-matrix3)all of them originate from mesenchyme-embryo
2、nalCT4)havefunctionsofconnection,supporting,protecting,nutrition,defenceandrepairingmesenchyme-mesenchymalcell:/structure:stellateinshapedwithprocessesa large nucleus,with clearnucleolesslightbasophiliccytoplasm/function:a.undifferentiatedcellb.multipledevelopmentalpotentialCT cell,SM andendothelial
3、cell-matrix2.Classification-CT in narrow sense means connetiveproper which include loose CT,dense CT,adiposeTandreticulartissue-CTinwidesenseincludescartilage,boneandblood3.Loose connective tissue(areolartissue)features:have more types ofcells and lessfibersfunctions:connection,supporting,defenceand
4、repairingconsistsofcells,fiberandgroundsubstance1)cells:seven types of cells are present in LCT fibroblast-structure:LM:large,flattenedcellwithprocesses-stellateinshapedLarge ovoid pale nucleus-contain more finechromatin,withclearone-twonucleoliWeaklybasophiliccytoplasm-homogeneousEM:richinRER,Golgi
5、appatatusandfreeribosome-function:synthesize fibers and groundsubstanceSynthesisofcollagenousfiberThreesteps:a.synthesisofprocollagen(RER)process(Golgi)outofcellb.procollagentropocollagenfibrilc.fibrilcollagenousfiber*fibrocyte:stillstateorinactivefibroblast-structure:spindle-shaped,smallN:small,dar
6、kstainedAcidophiliccytoplasmaEM:lessorganelles-function:becomeintofibroblastforrepairingmacrophage-structure:LM:round or ovoid-irregular in shape when it haveshortbluntprocesses_pseudopodiumSmallanddarknucleusAcidophiliccytoplasmEM:richina.lysosomeb.Phagosomephagocytosisandpinosomepinocytosisc.Remna
7、ntd.Microfilamentandmicrotubule-function:a.Chemotaxis:chemotacticfactorb.phagocytosis:Special phagocytosis:recognize Bacterium,virusandforeigncellnonspecial:carbonparticles,dustanddeadcells*Phagosome(pinosome)+primarylysosomesecondarylysosomeremnantsc.secretion:lysozyme,complementandinterleukin-I(IL
8、-1)andinterferon(INF)b.antigenpresentingfunction:*captureantigenprocesses+MHCIImolecule(majorhistocompatibilitycomplexmolecules)antigen-MHCIIcomplexesTLCplasmacell-structure:LM:roundorovoidRound eccentrically-located nucleus withmorespot-likedheterochromatinBasophiliccytoplasmEM:rich in parallelly a
9、rranged RER,freeribosomeandGolgicomplex-function:synthesizeandsecreteimmunoglobulin,Ig-antibodymastcell-structure:LM:roundandlargecellSmalldark-stainednucleusBasophilicsecretinggranulesBasophilicsecretinggranules:heparin:ananticoagulantHistamine:cause cap.permeability,cap.leakagetoformoedemaandcontr
10、actionofSMEosinophilchemotacticfactorCytoplasmcontain:leukotriene-slowreactionsubstance-function:causeallergicreactionfatcell-structure:large,roundorpolygonalflattenedovoidnucleuslocatedononesideofcellthinlayerofcytoplasmalargelipiddroplet-function:synthesizeandstorefatundifferentiatedmesenchymalcel
11、l-structure:similartofibrocyto-function:multidifferentiatingpotentialleukocytes:neutrophil,acidophilandlymphocyte2)fiberscollagenousfiber(whitefiber)LM:1-20umindiameterBelt-likedwaveandbranchtoformanetworkEosinophilicEM:parallel-arrangedfibrilsFibril:20-200nmindiameterHaveperiodiccrossstriationat64n
12、minterval*formation:Extracellularpolymerizecollagen(typeIandIII)collagenousfibrilcollagenousfiberelasticfiber(yellowfiber)LM:thinnerandless,0.2-1.0umSlight red(HE),purple(aldehyde fuchsin)orbrown(orcein)BranchandformanetworkEM:core:elastin-lowelectrondensityPeripheral:microfibril10-12nm,electrondens
13、efibrillinreticularfiberLM:thinandless,0.2-1.0umindiameterBranchtoformnetworkArgyrophilicfiber(silverimpregnationmethod)EM:typeIIIcollagen64nmcrossstriation-distribution:reticulartissueconnectingportion,e.g.reticularlamina3)groundsubstance-amorphouscolloidalsubstance-consistsofproteoglycan,glycoprot
14、einandtissuefluidproteoglycan-largemolecularcomplex-glycosaminoglycans:chondroitinsulfatekeratinsulfatedermatansulfateheparinsulfatehyaluronicacid:2.5umlong-protein*molecularsieveglycoprotein:proteins-fibronectincellsfibronectincollagenproteoglycan-laminin-chondronectin-function:Connectionaffect the
15、 differentiation and movement ofcellstissuefluidtissuearteryTissuefluidveinbloodsteamcellsdehydrationoedema4.Denseconnectivetissue-morefiber-connectionandsupporting1)regularDCT:parallelly-arrangedcollagenousfiberstendoncells:/specialfibroblast/wing-likedprocesses-distribution:tendons,ligamentandcorn
16、ea2)irregularDCT:Fiberarranged inbundles,runingindifferentdirectionFibroblastlessgroundsubstance-distribution:dermis,sclera and capsule ofsomeorgans3)elasticT:elasticfiberinbundlesorinmembraneligamentandlargeartery5.adiposetissue-LCT+fatcells-whitefatT:singlefatcelldistributioninsubcutaneoustissue,m
17、esenterium-brownfatT:fatcellcontainmanysmalllipiddroplets,richinlargemitochondriacentrally-locatednucleusrichincap.distribution:neonate6.reticulartissue-reticularcells:stellatewithprocesses-formnetworkround,ovoid and pale nucleus with 1-2nucleoliEM:richinRER-reticularfiber:connecttoformnetwork-distribution:hemopoietictissueandlymphatictissue