e07.Nervous-tissue神经组织(ppt文档).ppt

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 7 Nervous tissue 1.Generaldescription:-Components:nervecell:neuronGlialcell:neuroglial-Function:Neurons:receivethestimulation,conductthenerveimpulseGlial cell:support,protect and insulate,nourishneurons2.Neuron The structural and functional cellular unit1)shapeofneuron:consistsofcellbody,dendriteandaxon-cell body:spherical,pyramidal fusiform orstellateinshape,5um-150um-dendrite:likebranchesoftree-axon:longthincord-liked2)structureofneuroncellbody:-cellmembrane:unit membrane-irritability,receive stimuli,initiateandconductnerveimpulsemembraneproteins-ionschannelandreceptor-cell nucleus:large and round,centrally-located,lessheterochromatin,sopalestained,withalarge,clearnucleolus-cytoplasm:perikaryona.Nisslbody:LM:basophilicspot-likedorgranule-likedstructureEM:parallelly-arrangedRERandfreeribosomefunction:synthesisofproteinsstructuralproteinenzymesrelatedtotheproductionofneurotransmittersb.Neurofibril:LM:insilverimpregnationmethods(silverpreparation),there are manythread-liked darkbrowncolorstructure to formanetwork.EM:neurofilament:10nmindiametermicrotubule:25nmindiameterfunction:supportinginvolvinginintracellulartransportationc.otherorganelleGolgiapparatusmitochondriapigmentdendrite:-many,shortandmorebranches-structure:similartocellbody-dendritic spine(places for formation ofsynapse)andspineapparatus(structureformedby2-3layersSER)-function:receivetheinformationaxon:-thin,lessbranch-structure:noNisslbody,buthavemicrotubule,neurofilament,microfilament,mitochondria,SERandvesicleaxonhillock:thebeginningpartofaxonaxolemmaaxoplasm-function:initiateanimpulseandconducttheimpulse*axonaltransports:slow anterograde:cytoskeletalprotein:microtubule,microfilamentandneurofilament(0.1-0.4mm/d)fastanterogradesynapticvesicles,enzymesandproteins(100-400mm/d)fastretrograde:productsofmetabolism,intaking materialsincludingproteinorneurotrophicfactors(100-400/d)3)classification:-Accordingtonumberofprocessesmultipolarneuronbipolarneuronpseudounipolarneuron-AccordingtolengthofaxonGolgitypeIneuron:longaxonandlargeGolgitypeIIneuron:shortaxon-Accordingtofunctionsensoryneuronmotorneuroninterneuron-According to the neurotransmitter orneuromodulatorreleasebytheneuroncholinergicneuronaminergicneuronpeptidergicneuronaminoacidergicneuron3.synapse-definition:is the junctions betweenneuronsorneuronandnon-nervecellsclassification:chemicalsynapse:takingneurotransmitterascommunicatingmediumelectricalsynapse:gapjunction-structureofchemicalsynapse:LM:insilverpreparation,therearemanybutton-likedstructuresonthesurfaceofdendritesandcellbody,calledsynapticbuttonEM:/presynapticelement:axonalterminalpresynapticmembranesynapsevesicle:-roundorflattened,40-60nm-clearorwithelectrondensecore-containneurotransmitters:acetylcholine,Achnorepinephrine,NEdopamine,DA-neuromodulator:peptides-changethereactionofneurontoneurotransmitter,modulateneurotransmittersubstancePenkephalinvasoactiveintestinalpolypeptide,VIPtherearesynapsinImito,SER,microtubuleandmicrofilament/synapticcleft:15-30nm/postsynapticelement:-postsynapticmembrane-receptorsClassificationofchemicalsynapse:/Accordingtofunction:excitatorysynapseinhibitorysynapse/Accordingtostructure:type I:postsynaptic membrane isthicker than presynaptic membrane,withwidesynapticcleft(excitatorysynapse)typeII:therearelesselectrondensematerialattachedonsynapticmembrane,thethicknessofpostsynaptic membrane is same topresynapticmembrane(symmetricalsynapse)4.Glial cell(neuroglia)1)GlialcellinCNS(centralnervoussystem)a.Astrocyte:/largestellate/round or ovoid nucleus,large and pale(euchromatin)/gliafilament:intermediatefilament/end feet:to form glia limitans or vascularfeet-constitutebloodbrainbarrier/classificationfibrousastrocytes:-white matter,have long,thin andsmoothprocesses-moreglialfilament-glialfibrillaryacidicprotein,GFAPprotoplasmicastrocyte:-graymatter,short,thickprocesseswithmorebranch-lessglialfilament/function:.supporting,insulatingandrepairingii.regulatetheenvironmentandmovementofneuroniii.secret neurotrophic factor:nervegrowthfactor,NGF,ciliaryneurotrophicfactor,CNTP and glial cell line-drivedneurotrophicfactor,GDNFb.Oligodendrocyte:-structure:smaller,fewer process with asmallroundanddarkstainedN-function:i.theirprocessesformmyelin-sheathofNFinCNSii.inhibitegrowthofprocessesofneuron(secreteinhibitingfactor-NI-35,NI-250myelin-associatedglycoprotein)c.Microglia:-structure:smallest,elongateshapeorovoid,withasmalldarkirregularN-function:phagocytosis-mononuclearphagocytesystemd.Ependymalcell:-structure:simplecuboidalorcolumnarepiapical:microvilliandciliabasal:longprocesses-tanycyte-function:producecerebrospinalfluidnervestemcellinorunderependyma-distribution:ventricle of brain and centralcanalofspinalcord2)glial cell in PNS(peripheral nervoussystem)a.Schwanncell:/envelop the axon end to end to formmyelin-sheathinPNSand/produce NGF,CNTF and BDNF(brainderivedneurotrophicfactor)b.Satellitecell(capsularcell):/onelayerofflattenedorcuboidalcell,withround,ovoidanddarkN/surroundingtheNeuroninganglion5.NervefiberandNerve-definition:astructureformedbyaxonandglialcellcanconducttheimpulsetocertaindirection-classification:according to myelin-sheathmyelinatednervefiberunmyelinatednervefiber1)MNFMNFinPNSLM:Axonmyelin-sheath:HE:net-liked;OsO4(osmiumtetroside)fixation and stain:black withSchmidt-Lantermannincisureneurilemma:cellmembraneofSchwannandbasementmembrane*Ranvier node:narrow part,no myelin-sheath-saltatoryconduction*internode:thesegmentofNFbetweentwoRanviernodesEM:Schwanncell(neurilemmalcell):Schwanncellinvaginationandenvelopthe axon form mesaxon mesaxonbecome longer and longer spiral aroundthefibertoforcetheNandcytoplasmgototwoside,innerandoutedgesconnectingwithincisureMNFinCNS-structure:similartoinPNSmyelin-sheathformedbyflattenedendingofoligodendrocytesprocessesoneoligodendrocytecanenvelopmanyaxonsnoincisureandbasementmembrane2)N-MNFN-MNFinPNS-structure:thinaxonandSchwanncellconnectendtoendnomyelin-sheathandRanviernodeoneSchwanncellenvelopsmoreaxonsN-MNFinCNS*nothingtoenveloptheaxon-nakedaxon3)Nerve-NervefibergetstogethertoformnerveefferentNafferentNmixedN-structure:epineurium:DCTperineurium:-twolayers:/outerlayer-CT/inner layer-several layers ofSSE-perineuralepithelium(tightjunctionandbasementmembrane)endoneurium:thinlayerofLCT6.Nerve Ending1)Sensorynerveending-peripheral processes of pseudounipolarneuron+other structure to form sensoryreceptorfreenerveending-structure:NFlosemyelin-sheathbranchdistributeinepidermis,cornea,hairfollicleepithelialcellandCT-function:feelcold,hot,painandslighttouchEncapsulatedNending-haveCTcapsulea.tactilecorpuscle-structure:ovalCTcapsuleflattenedcell-transversearrangedNFlostmyelin-sheathspiralflattenedcells-distribution:dermalpapillae,especiallyintipoffingerortoe,palms,solesandlips-function:touchreceptorsb.lamellarcorpuscle-structure:large,ovalorsphericalcapsule:several layers of flattened cellconcentrically-arrangedbulb-cylindricalNFlostMSenterthebulb-distribution:subcutaneous T,mesentery,ligament-function:feeldeeporheavypressurec.Muscularspindles-structure:fusiformCTcapsuleafewsmallmusclefibers-intrafusal musclefiberNF:rollupthemuscleF-distribution:skeletalmuscle-function:detectmusclelengthandchangeinmusclelength2)Motornerveending:muscularTandglandSomatic MNE:motor end plate,neuromuscularjunction-structure:EMmuscleF:richincytoplasm,nucleiandmitopresynaptic membrane:-synaptic vesicles-achtylcholinesynapticcleft:postsynapticmembrane:-synapticgatter-junctionalfolds-typeNreceptor*motor unit:axon of one neuron and allskeletalmusclefibercontrolledbyitVisceralMNE-lateralhornneuronaxon(preganglionicfiber)ganglianeuronornerveplexusaxon(postganglionicfiber)-structure:NF are thin,no MS form varicosity(roundgranules-likedvesicles)*vesicles:acetylcholine-round,Clearnorepinephrine,NE-granules-likedglycine-flattened,clear-distribution:smoothM,CardiacMandgland