physiology - male reproduction pp lecture生理学男性生殖讲座

Chapter12ReproductionDongJing(董静)

Dept.Physiology

QingdaoUniversityEmail:.cnMaleReproductionSpermatogenesis:formationofspermEndocrinefunctionsoftestisRegulationoftestisfunctionSection1

Testisendocrineandmalereproductivephysiology

一、Maleprimarysexorgan:Testis

SpermatogenesisofTestis（一）Theprocessofspermatogenesis（二）Thetransportofspermsandejaculation

MaleReproductiveAnatomyandPhysiologyTestisEpididymisVasdeferensSeminalvesicleProstateBulbourethralEjaculatoryductUrethraPenisMaleReproductiveAnatomyandPhysiologySertoliCellFunctionSertoliCellsNourishhealthycells&phagocytizedamagedgermcellsSynthesizeluminalproteinsMaintaintubularfluidConvertandrogenstoestrogensAresiteforhormonalmodulationoftubularfunctionMajorTesticularSteroids()=RelativeactivitywhereTactivity=100AndrogensareC19steroidsMajorityof5a-DHTisformedinperipheraltissuesMaleSexSteroidSynthesisCholesterolmaybefromplasmaordenovosynthesisTmaybeconvertedinperipheraltissuestoestradiol&androstenedioneAndrostenedioneisthemajorsourceofestradiolinmenDelta-5pathwayisthemajorrouteinmenTransportofSexSteroidsinMalesMajorSexSteroidBindingProteinsTestosterone-EstrogenBindingProteinOnehighaffinitybindingsite(T1/2=22seconds)Bindingaffinityorderforsexsteroids=DHT(100)>T(33)>E(25)AlbuminOnelowaffinitybindingsite(T1/2-=1second)CortisolBindingGlobulinNobindingtoDHT,TorE2.BindsProgesteroneNormalDistributioninBlood

TEBG(30%),Albumin(68%),Free(2%) Activefractionincludesfree+albumin-boundfraction

AndrogenActivityIncreasedSpermatogenesisIncreasedBoneGrowthIncreasedbonematrix,calciumdepositionandpromotesepiphysealclosureIncreasedNitrogenBalanceIncreasedmusclemass,larynxsizeIncreasedatheleticperformanceIncreasedbasalmetabolicrate,redbloodcelldensityoxygenutilizationAlteredSkinFunctionIncreasedthickness,melanindepositionsebaceousglandsecretionSpermatogenesis:

SpermProductionintheTestisSeminiferoustubulesSpermatidsSpermatocytesSpermatozoaSertolicellsInterstitialtissueLeydigcellsCapillariesSpermatogenesisSpermatozoaStructureandFunctionsinReviewFigure26-10:SpermstructureHeadAcrosome:Nucleus:MidpieceCentrioles:Mitochondria:Tail:flagellumMicrotubules:GnRH

LH

Leydigcells

testosterone

20sexcharact.GnRH

FSH

Sertolicells

spermatoctyematurationInhibinfeedback–FSH,testosterone–short&longloopsRegulationofSpermatogenesisTheregulationoftestesfunctionsFigure26-11:HormonalcontrolofspermatogenesisControloftestesfunctionsbyhypothalamusandpituitaryFeedbackregulationoftesteshormonesHypothalamic-PituitaryregulationofTesticularFunctionFemaleReproduction,PregnancySexualDifferentiation&GrowthFemaleReproductiveAnatomyandPhysiology:OverviewOvaryFallopiantubeFimbriaeUterusCervixEndometriumVaginaClitorisLabiaFemaleReproductiveAnatomyandPhysiology:OverviewFigure26-12b:ANATOMYSUMMARY:FemaleReproductionTwocell-twogonadotropinschemePhysiologicaleffectsofestrogenEstrogen-Uterus-Ovary-Vagina-Breast-MetabolismFollicularStructureOvary:DetailsofHistology&PhysiologyFigure26-12d:ANATOMYSUMMARY:FemaleReproductionMenstrualCycle:EggMaturation,andEndometrialGrowthFollicularphaseEggmaturesOvulationEggreleasedLutealphaseCorpusluteumEndometriumPrepforblastocystNoPregnancyMensesFollicularGrowthRegulationGnRHrisesinresponsetoadeclineininhibinandsexsteroidsGnRHstimulatesriseinpituitaryFSH&LHsecretion.FSHstimulatesnewfolliclegrowthLHinducesthecalcellgrowth,vascularization&androgensynthesisFSHstimulatesgranulosacellproductionofE2&LHreceptorFollicularGrowthRegulation2LHactonthecal&granulosacellsandFSHactsongranulosacellsLatefollicularphasehaselevatedfollicularfluidE2,P,FSHandLHbutlowandrogensFollicularphaseOvulationLutealphaseovariancycleFSHstimulatesfolliculardevelopmentEstrogen:+feedback,limitsmorefolliclesEndocrineControlofMenstrualCycle:

FollicularPhase

Estrogen

LH"surge"&FSHspike

eggreleaseInhibin

pushesFSHdown,

newfollicledevelopmentEndocrineControlofMenstrualCycle:OvulationOvulationThestigmata,acone-shapedprotrusionofthefolliclewall,appearsjustbeforeovulationPreovulatoryfollicularfluidhaselevatedE2,P,FSH,LH,oxytocin,plasminactivity&collaginaseactivityExtensivefollicularvascularizationoccursimmediatelypriortoovulationFigure26-14a,b:HormonalcontrolofthemenstrualcycleEndocrineControlofMenstrualCycle:

FollicularPhaseandOvulationGranulosacellsformcorpusluteum

progesterone

progesterone&estrogenmaintainendometriumInhibincontinuestolimitnewfolliculardevelopmentEndocrineControlofMenstrualCycle:LutealphasePregnancy:maintain

progesterone,estrogen&inhibinNopregnancy:

progesterone,estrogen&inhibinMenses,

FSH&LH

newfollicledevelopmentEndocrineControlofMenstrualCycle:

LateLutealphaseEndocrineControlofMenstrualCycle:

LutealphaseandLateLutealphaseFigure26-14c,d:HormonalcontrolofthemenstrualcycleOverviewoftheMenstrualCyclePlacentaandFurtherEmbryonicDevelopmentFigure26-19a,b:TheplacentaBirth:ParturitionLabor (initiatedbyafetalsignalRhythmic (stretchinducesreleaseofoxytocin)Uterine (oxytocincontinuesuterinecontractionsContractionsCervicaldilation (inducedbyrelaxin)Delivery BabyPlacentaBirth:ParturitionFigure26-20:Parturition:thebirthprocessRegulatorsofParturitionFigure26-21:ThepositivefeedbackloopofparturitionLaboronsetStretchstimulusOxytocinProstaglandinsPositivefeedback

Stretch

OxytocinBirthendsStimulusLactation:ProducingandReleasingMilkEstrogen&progesteronePrepsmammarytissuesProlactininhibitingH:Prolactin

milkproduction(otherrolesinfertility)Suckingstimulus

Oxytocin

"Milklet-down"reflexLactation:ProducingandReleasingMilkFigure26-23:ThehormonalcontrolofmilksecretionandreleaseReproductiveMaturation:PubertyIncreaseproductionofsexhormonesMaturationofreproductiveorgans&gameteproduction20sexualcharacteristicsMales:pubichair,beard,deepvoice,"wedge"bodyform&

musclemassFemales:menarche,pubichair,breasts&"pearshape"bodyformLaterinLifeMenopause:Female"Change-ofLife"Ovaries

respondingtoGnRH

Levelsofestrogen&progesteroneproducedCeaseeggdevelopment"Hotflashes",

osteoporosisrisk(hormonereplacementdebate)"Andropause"(?):Malechangesaregradual

Sexhormones:

musclemass,

libido,

erectionsViagra:PNS

NO

cGMP

degradationChapter12ReviewquestionMenstrualcycle:Puberty:Duringthelatefollicularphase,plasmaestrogenincreasestoelicitasurgeofwhichkindofhormone,whichthencausesovulation.Thehighlevelsofprogesterone,inthepresenceofestrogen,inhibitthesecretionofGnRHandtherebythatofthegonadotropins,sothat

menstruationdonotoccur.Chapter4CardiovascularPhysiologyKeyTerms1)fastresponsecell,2)slowresponsecell,3).autorhythmiccell.(autorhythmicity)4).Diastolicdepolarization.5)pacemaker(dominant

,latent

,ectopic

),6)prematuresystole(extrasystole),7)compensatorypause,8)positive/negativechronotropicaction,9)atrioventriculardelay,10)positive/negativedromotropicaction,11)positive/negativeinotropicaction,12)cardiaccycle,13)systole/diastole,14)cardiacoutput.,15)Strokevolume;16)ejectionfraction,17)cardiacindex,18)enddiastolicvolume(EDV),19)Starling’slawoftheheart(heterometricautoregulation),20)homometricregulation;21)Meanarterialpressure;22)Centralvenouspressure,23)effectivefiltrationpressure,24)sympatheticvasoconstrictortone,25)rostralventrolateralmedulla(RVLM),26)baroreceptorreflex,27)rennin-angiotensinsystem(RAS),ReviewQuestions

1.Describetherelationshipbetweenflow,pressure,andresistanceinthevascularsystem.2.DescribetheStarlingforcesthatdeterminethenetmovementoffluidacrossthecapillarywall.Defineflow-limitedexchangeanddiffusion-limitedexchange,anddescribethevariationsincapillarypermeabilityandstructureseenindifferentpartsofthebody.3.StatethePoiseuille–Hagenformulaforflowinbloodvessels,andexplainonthebasisofthisformulawhytheradiusofavesselissuchanimportantdeterminantofflow.4.WhatisaWindkessel?WhyaretheaortaandlargearteriescalledWindkesselvessels?WhatisthephysiologicsignificanceoftheWindkesseleffect?ReviewQuestions

5.Ayoungmanhasabloodpressureof130/73mmHg.Whatishispulsepressure?Whatishismeanarterialpressure?Howdidyoucalculateeachofthesepressures?6.Ittakesseveralmonthsfornervestogrowintotransplantedhearts.However,beforethenervesregrowinpatientswithtransplantedhearts,exerciseincreasestheircardiacoutput.Whatisthemechanisminvolved,andhowdoesitoperate?7.Whatistheejectionfraction?Whichconditionscauseittoincrease,andwhichconditionscauseittodecrease?Why?ReviewQuestions8.Nametheprincipalhormonesthataffectarterialbloodpressureandthephysiologicroleofeach.9.Outlinetheneuralmechanismsthatcontrolarterialbloodpressureandheartrate,includingthereceptors,afferentandefferentpathways,centralintegratingpathways,andeffectormechanismsinvolved.10.

Whydoesincreasedsympatheticactivitycauseanincreaseinrightatrialpressure?Whatarethemechanismsandpathwaysinvolved?11.

Whichhormonesaffecttheheartrateandhowdotheyproducetheireffects?Chaper9SensoryPhysiology

KeyTermsreceptorpotential,2)adequatestimulus,3