分子細胞生物學課件：05 cartilage and bone

CartilagecartilageCartilagetissue

ChondrocyteIntercelluarsubstancesFiberGroundsubstanceCollagenfibrilhyalinecartilageElasticfiberelasticcartilageCollagenfiberfibro-cartilageperichondriumConncectivetissue,containgchondroblasts(1)ChondrocyteLocation:atthecartilage

lacunaeStructure:LM:clearnucleoli,basophiliccytoplasmEM:abundantRERandGolicomplexFunction:synthesizeboththegroundsubstanceandfibersdividetoformclustersofchondrocytes(isogenousgroup)Interstitialgrowth(2)IntercellularsubstanceGroundsubstance:acidsulphatedglycoproteinsbasophilicFibers(3)PerichondriumConncectivetissue,containgchondroblastsChondrocytedifferenciateAppositionalgrowthProtection,providenutrition,HyalinecartilageTheintercellularsubstanceisamorphous:thegroundsubstanceandcollagen(typeIIcollagenfibril)havesimilarrefractiveindices.CartilagecapsuleIsogenousgroupPerichondriumNumerousbundlesofelasticfibersinthecartilagematrixElasticcartilagenumerousbundlesofcollagenfibersinthecartilagematrixFibrocartilageBoneBoneOsseoustissueExtracellularmatrixOrganicInorganicCellsOsteoprogenitor/osteogeniccellosteoblastosteocyteosteoclastOsteumBonemarrowFunctions:supportandprotection

participatethemetabolismofcalciumandphosphateions（bonematrix）Redmarrow(active)Yellowmarrow(inactive)BonematrixOrganiccomponentCollagenfibersGroundsubstance:Glycoproteins,etc.Inorganiccomponent：bonemineral,hydroxyapatitecrystals（Ca10[PO4]6[OH]2)

Collagenfiberslieparalleloneanotherinthegroundsubstancewiththebonemineraldeposition.

osseoustissue（osteoid）BonelamellaDiagramoftheosseoustissueosteoblastosteoprogenitorosteocyteosteoclastBonelacunaeBonelamella1、osteoprogenitor/osteogeniccell

Location：surfaceoftheosseoustissue

Functions：bonegrowthcontinuousremodellingrepairofbonefracturesCells2、osteoblast

Location：surfaceoftheosseoustissueLM:basophiliccytoplasm,palestainednuclearwithaprominentnucleolusEM:abundantRERandGolgiC.

Functions:synthesizethebonematrix

(collagenfiber,glycoproteins,etc.)

3、osteocyte

Location：inthebonelamellacellbody---bonelacunaecytoplasmicextensions-----canaliculi

Structure:gapjunctionsbetweentheextensionsFunctions:maintainthedynamicstateofthemineralisedbonematrix;maintainthecalciumhomeostasisBonelemellaandosteocyteOsteocyteBonelamellaBonelacunaeBonecanaliculiCentralcanal4、osteoclast

Localization：depressionsresorbedfromthebonesurfaceLM:multinulei,acidophiliccytoplasmFunctions:osteoclasticresorptioncontributestoboneremodelling;maintainthebloodcalciumhomeostasis(responsetoparathyroidhormoneandcalcitonin)OsteoclasticresorptionCa2+(-)Ca2+DiagramoftheosseoustissueosteoblastosteoprogenitorosteocyteosteoclastBonelacunaeBonelamellaLongboneOsseoustissuePeriosteum,endosteumMarrowcavityArticularcartilageBloodvesselsandnervesspongybonecompactbone19epiphysisepiphysisdiaphysisSpongeboneConsistsofanetworkoffine,irregularplatescalledtrabeculaeseparatedbyintercommunicatingspacescontainingbonemarrowTrabeculae:thin,irregularbonelemellawithosteocyteinsidelinedbyendosteumtrabeculaeBonemarrowCompactboneCircumferentiallamellaOuterInner:irregular

Osteon(Haversiansystem)LayersofconcentricbonelamellaedisposedaroundHaversiancanalcontainingblood,lymphaticvesselsandnerves.TheHaversiancanalsinterconnectwithoneanother,andwiththeendosteumandperiosteumviaVolkmann’scanals

interstitiallamellaIrregularlamellaebetweenintactHaversiansystemsduetoresorptionoftheformerHaversiansystemsDiaphysisoflongboneInnercircumferentiallamellaosteonInterstitiallamellaOutercircumferentiallamellaperiosteumCentralcanalendosteumCentralcanalPerforatingcanal(Haversiancanal)(Volkmanncanal)(Haversiansystem)BoneOsteonCompactboneosteum

Periosteumouter：denseconnctivetissue

(perforatingfiber/Sharpey’sfiber)inner：abundantvesselsandcells

（osteoprogenitorandosteoblast）Endosteum:richinbloo