睾丸的内分泌作用间质细胞interstitialcellsofLeydig

GeneralprincipleGonadsOvariesTestesTestosteroneSecreteSecreteProduceProduceSpermatozoe/SpermsOva/EggsEstrogen+ProgesteroneGametesOthersourcesofsexhormonesTestosterone:adrenalcortexEstrogenandProgesterone:placenta,adrenalcortex,adiposetissueMalereproductionsystemPrimaryorganGonadTestisAccessoryorgansExternalstructures:penis,scrotum,epididymisInternalstructures:vasdeferens,seminalvesicles,prostateglandandbulbourethralglandsFemalereproductionsystemPrincipalorganOvaries(primarysexualorgan)AccessorysexualorgansFallopiantubesUterus-cervixvaginaGeneralhormonecontrolofreproductionGonadotropin-releasinghormoneLuteinizinghormoneFolliclestimulatinghormoneMaleReproductiveFunctionTestis（睾丸）Seminiferoustubules（生精小管）Spermatogonia（生精细胞）Sertolicells（支柱细胞）:facilitatespermatogenesisLeydigcells（interstitialcells）:secretetestosteroneTestisFunctionsSpermatogenesis（生精作用）EndocrinefunctionsSpermatogenesisSteps:Spermatogonia(undifferentiatedgermcell)Sexchromosomes(XandYchromosomes)BegintodividemitoticallyatpubertyPrimaryspermatocyteMeiosisISecondaryspermatocyteMeiosisIISpermatidSpermatozoa(sperm)MalespermFemalespermSpermSperm(30~120millionsperm/day)HeadAcrosome:enzymesTail(flagellum)ToandfromovementThesmallestandlargestcellsinhumanSperm:3μmindiameterwiththeflagellumupto50μmlongOvum:1000μmindiameterSpermatogenesisInalltheseminiferoustubulesduringactivesexuallifeStimulatedbygonadotropichormonesBeginatanaverageageof13yearsDecreasingmarkedlyinoldageTheentireperiod:64daysManufacture30millionspermperdaySemenSpermcountEjaculatedsemenduringeachcoitus:3.5mlAnaverageofabout120millionsperm/mlsemen35~200million/ml<20million/ml

infertilePenisEngorgementofthepenisduringsexualexcitementisduetoactivationofthereflexpathwaysforerection.Nitricoxideisanimportantvasodilatorinthisreflex.ErectionPrevalenceofEDErectiledysfunction(ED),orimpotenceaproblemattainingormaintaininganerectionSexhormonesSynthesisFromcholesterolMostabundantMostpotent(DHT)AndrogensAndrogensTransportation+Albumin+Gonadalsteroid-bindingglobulin(GBG)MetabolismTDHT(tissue)orEstrodiolDegradationintoinactiveproductsintheliverExcretionFromthekidneyorgutFunctionsoftestosteroneStimulusfordescentofthetestesThetestesusuallydescendintothescrotumduringthelast2to3monthsofgestation.Ifundescended,administrationofTorgonadotropichormonesInducedifferentiationofmaleaccessoryreproductiveorgansandmaintaintheirfunctionRequiredforinitiationandmaintenanceofspermatogenesisFunctionsoftestosteroneInducemalesecondarysexualcharacteristicsinpubertyFunctionsoftestosteroneEffectonthevoiceCausinghypertrophyofthelaryngealmucosaandenlargementofthelarynxArelativelydiscordant“cracking”voicetypicaladultmasculinebassvoiceEffectontheskinanddevelopmentofacnethicknessoftheskinsecretionbythesebaceousglands（皮脂腺）FunctionsoftestosteroneEffectonmuscledevelopmentmusclemassSyntheticandrogensUsedbyathletesUsedinoldage asa“youthhormone”FunctionsoftestosteroneEffectonbonegrowthandcalciumretentionsizeandstrengthofbonestotalquantityofbonematrixCausescalciumretentionOftenusedinoldermentotreatosteoporosisSpecificeffectonthepelvisAfunnel-likeshapeFunctionsoftestosteroneEffectonfatdepositionEffectonmetabolismStimulateproteinanabolismEffectonredbloodcellsredbloodcellsRequiredforsexdriveandmayenhanceaggressivebehaviorRBCHbman4.0~5.5x1012/L120~160g/Lwoman3.0~5.0x1012/L110~150g/LRegulationoftestisfunction

Hypothlamus-pituitary-testisaxisHypothlamusGnRHPituitaryFSH(+)SpermatogenesisLHTsecretionTestisT:negativefeedback(-)LHInhibin:negativefeedback(-)FSHProcessoffertilizationEjacuationdepositssemenintothevagina.Spermsarrivefallopiantubewhereeggresides.Capicitationofsperms.Aspermbindstothezonapellucidaofanegg.Acrosomereactionoftheboundspermtodigestapaththroughthezonapellucida.Whenthespermreachestheplasmamembraneoftheegg,itfuseswiththemembraneoftheeggandpassestheheadintothecytosoloftheegg.Theegg,afterfusionwiththefirstsperm,hasacorticalreactiontoblockthefurtherfusionofothersperms.Capacitationofspermatozoa

（精子获能）OccursinthefemalegenitaltractIsstimulatedbysecretionsinthevagina,uterus,anduterinetubesResultsincapacitytopassthroughthecoronaradiataInvolvesremovalofsurfacecoatingsandchangesinplasmamembraneAcrosomereaction（顶体反应）Isstimulatedbysperm-bindingglycoprotein moleculesinthezonapellucidaIsaccompaniedbyCa2+influxintospermInvolvesfusionoftheacrosomemembraneandplasmamembraneResultsinthereleaseofacrosomalenzymes(hyaluronidaseandproteolyticenzymes)IsnecessaryforspermpenetrationthroughthezonapellucidaThecellmembranesofthespermheadandoftheoocytefusewitheachothertoformasinglecellThegeneticmaterialofthespermandtheoocytecombinetoformacompletelynewcellgenome,containingequalnumbersofchromosomesandgenesfrommotherandfatherFertilizationTwoimportantgeneticconsequencesThediploidchromosomenumberisrestored(2n)Thegeneticsexofthezygoteisdetermined(XXorXY)Thespermatozoadeterminethesexoftheembryo.ThereareX-bearingspermatozoaandY-bearingspermatozoa.TheoocytealwayscontributesanXchromosome.OvaryFunctionOogenesisEndocrinefunctionsSteroidhormonesProductionofhaploidgametesinfemalesiscalledoogenesis.Thefullsequenceofmeiosisisnotcompleteduntilfertilization.OogenesisThedevelopmentofanovarianfollicleandoocyteTheovariescontain2to4millioneggs.Onlyafew(400)willbeovulatedduringawoman’slifetime.Alltheothersdegenerate.FormationoftheCorpusLuteumMenstrual/OvariancycleOvarianHormonesEstrogens（雌激素）Estrone（E1）Estradiol（E2）Estriol（E3）Progestins（孕激素）Progesterone（P,孕酮）OvarianHormonesSynthesisGranulosacellELuteincellP,EThetwo-stagemodelofestrogensynthesisholdsthatandrogenprecursorsaresynthesizedintheouterlayer(thecacells)oftheovarianfolliclesanddiffusetotheinnerlayer(granulosacells)forconversiontoestrogens;LHdrivestheformer,FSHthelatter.OvarianHormonesTransportinthebloodBindingwithPlasmaalbuminSpecificestrogen-andprogesterone-bindingglobulinsRapidlyreleasedtothetissuesAbout30minsFunctionsofestrogensFunctionsofProgesteroneMenstrualCycleMenstrualCycle:monthlyrhythmicalchangesintheratesofsecretionofthefemalehormonesandcorrespondingphysicalchangesintheovariesandothersexualorgans(e.g.,theuterus)OvariancycleOnlyasingleovumisnormallyreleasedEndometriumcycleUterineendometriumispreparedinadvanceforimplantationofthefertilizedovumLength:averageabout28daysStartatpubertyMenarche:11~15yearsofageStopatmenopause40~50yearsofageOvariancycleOvariancycleFollicularphase:Day1today14AsinglematurefollicleandsecondaryoocytedevelopE

Lutealphase:Day15today28FormationofthecorpusluteumPandE

CorpusalbicansOvariancycleOvulationHappensonapproximatelyday14InducedbythemidcyclesurgeofLHExpulsionofthematureoocyteThesecondaryoocyte+zonapellucida+coronaradiata+theantralfluidaredischargedOvariancycleTheovariancycleofchangesinsteroidproductiondrivestherestofthechangesthatcharacterizethemenstrualcycleofadultfemales.Thefollicularphaseismarkedbyincreasinglevelsofestrogenswhereasthelutealphaseisoneofincreasedprogesteronelevels;thetransitionbetweenthetwoisovulation.EndometrialcycleEndometrialcyclePhasesProliferativephase

Day5–14OccurringbeforeovulationUndertheinfluenceofEsEndometriumthickness

SecretoryphaseDay15–28OccurringafterovulationUndertheinfluenceofEsandPEndometriumthickness

ToproduceahighlysecretoryendometriumthatcontainslargeamountsofstorednutrientstoprovideappropriateconditionsforimplantationofafertilizedovumMenstrualphaseDay1–5EndometrialcycleMenstrualphase:1-5daysCausedbythereductionofEandPTheendometriumdegeneratesMenstrualflowBlood+endometrialdebrisBloodloss:50to150ml/menstrualperiodNonclotting(releaseoffibrinolysin)RegulationofmenstrualcycleHypothalamic-pituitary-ovariansystemHypothalamusGnRH:FSHandLHPituitaryFSH:

Folliculargrowth,E,PsecretionLH:ovulation,corpusluteumformation,PsecretionOvaryE:negativeandpositivefeedbackeffectsP:negativefeedbackeffectSmallincreasesinthesecretionofgonadotropins(LH&FSH)leadtofollicularmaturation,includinganincreaseinthesynthesisandsecretionofovariansteroidhormones(1-7).OvulationisprovokedbyasurgeinLHandmarksthetransitiontothelutealphaseofthecycle,characterizedbyhighlevelsofprogesterone.(8-14).Eventually,(15)adecreaseinLHleadstoluteolysis,andthewithdrawalofsteroidsupportforathick,activeuterus.Menopause40~50yearsSexualcycle:irregular

ceaseTheremainingprimordialfolliclesbecomeatretic（闭锁）FemalesexHs

FSHandLHareproducedinlargeandcontinuousquantities.PhysiologicalchangesinthefunctionofthebodybecauseoflossofEsHotflushes（潮热）OsteoporosisIrritabilityFatigueAnxietyCardiovasculardiseasesincreaseToavoidseveresymptomsDailyadministrationofanEinsmallquantitiesandgraduallydecreasingthedosePregnancyFertilizationoftheovumThefusionofaspermandegginthefallopiantubeandtakesabout4daystoreachtheuterus.Thefertilizedeggiscalledazygote.PregnancyImplantationTheembeddingoftheblastocystintotheendometriumThemorulaisdifferentiatedintotwogroupsofcells-Theinnercellmassorembryoblast（成胚细胞）givesrisetotheembryo-Theoutercellmassortrophoblast（滋养层）giverise

totheplacentaandmembranesIn-VitroFertilizationRobertG.EdwardsUniversityofCambridgethe2010NobelLaureateinPhysiologyorMedicine,forthedevelopmentofinvitrofertilization,whichhassofarledtothebirthofaround4millionpeople.TheFatheroftheTestTubeBabyPregnancyPlacenta（胎盘）Aftertheendofthefirsttrimester,theplacentaismorefullydeveloped,includingitsnutritive/exchangerelationshipbetweenthematernalandfetalcirculations,anditssteroidproductsprovidehormonalsupportfortheuterus.PregnancyPlacentalhormones(producedbytrophoblastcells)Humanchorionicgonadotropin(hCG)Glycoprote