人体结构与功能 8-The hypothalamus and thermoregulation学习资料

Chapter1OrganizationoftheNervousSystemHypothalamusOutlineFunctionoftheHypothalamusRegulationofBodyTemperatureAutonomicNervousSystemI.FunctionoftheHypothalamusReferenceAdinaMichael-Titus,etal.SystemoftheBody–TheNervousSystem.2ndversion,ElsevierLimited,2011.P19–20姚泰主编，8年制及1年制临床医学等专用生理学，第二版，人民卫生出版社，2010年。P483–485。Tu:19.17

HypothalamusHypothalamicFunctionsFoodIntakeWaterBalanceSleep/wakecycleEmotionsandbehaviorCircadianEndocrineFunctionsBodyTemperatureAutonomicNervousSystemFoodIntakeVentromedialandParaventricularNucleiaresatietycentersLesioncausesobesityThroughdisruptingsatietyinputtotheperiventricularnucleusLateralHTisfeedingcenterStimulationcausefoodandwaterintakeLesioncausesstarvationbehaviorThroughdamagethemedialforebrainbundle,leadingtoneglectsyndrome–nomotivationtoeatWaterBalanceThirstcenterinthehypothalamus(supraoticnucleus)isstimulatedby:CellulardehydrationDecreasedsalivaryproductionIncreasedbloodosmoticpressureDecreasedbloodvolumeThirstcenterresponseReleasevasopressinCausesensationofthirstSleep/WakeCycle:suprachiasmaticnucisbiologicalclockpreopticnuccaninitiatesleeplatHTcanchangecorticalarousalpostHTlesioncancausecomaorimpairedarousalEmotionsandBehaviorVentromediallesionscancauseviciousness/ragePosteriorHTstimulatessympatheticfunctionsAnteriorHTstimulatesparasympatheticfunctionsMamillarynucleirecentmemoryAlmostalllandanimalscoordinatetheirbehavioraccordingtocircadianrhythmsSuprachiasmaticNuclei(SCN)CircadianCircadianRhythmsofPhysiologicalFunctions

EndocrineFunctionRegulationofAdenohypophysisSecretionofHormones(VasopressinandOxytocin)FunctionsoftheHypothalamusFoodintakeWaterbalanceSleep/wakecycleEmotionsandbehaviorCircadianEndocrineFunctionBodytemperatureAutonomicNervousSystemIIEnergymetabolismandbodytemperatureReferenceArthurC.Guyton,JohnE.Hall.TextbookofMedicalPhysiology,11thedition,ElsevierScience,2006.P881-900姚泰主编，8年制及7年制临床医学等专用生理学，第二版，人民卫生出版社，2010年。P483–485。Section1EnergyMetabolismmaterialsynthesismaterialbreakdownreleaseenergyrequireenergymaterialmetabolismenergymetabolismMetabolismAnabolismCatabolismEnergystorage,liberation,transferandutilizationEnergybalanceEnergyinput=energyoutputheatFoodheatheatATPcellularfunctionsheat

metabolismFoodheatMetabolicRateTheamountofenergyliberatedfromalivingorganismperunitoftimeExpressedintermsoftherateofheatliberationduringthechemicalreactionsMeasurementofthemetabolicrateDirectcalorimetryIndirectcalorimetryCaloricvalue/thermalequivalentoffoodOxygenconsumption/thermalequivalentofoxygen（1L）Respiratoryquotient（CO2/O2）FactorsthataffectthemetabolicrateExercise-increaseinmetabolicrateIngestionoffood-IncreasemetabolicrateThespecificdynamicactionofproteinEmotionalstateEnvironmentaltemperature20-30°Chavestablemetabolicrate<20or>30°C,metabolicrateisincreasedOtherfactors(sleep,sex,age,etc.)ComponentofEnergyExpenditureBasalmetabolicrate(BMR)minimumlevelofenergyrequiredtoexistapersonisatbasalcondition(completerest)usefulfordiagnosingthediseases:Hyperthyroidism,hypothyroidismBasalconditionsFastedforatleast12hoursAfteranightofrestfulsleepNostrenuousactivityisperformedforatleast1hourbeforethetestAllpsychicandphysicalfactorsthatcauseexcitementmustbeeliminatedThetemperature25–30°CNophysicalactivityispermittedduringthetestSection2BodytemperatureSkinandCoreTemperatureSkintemperaturethetemperatureoftheskinandtissuesimmediatelyunderlyingtheskin.risesandfallswiththetemperatureofthesurroundingsCoretemperature

thetemperatureofthedeeptissuesofthebody–the“core”ofthebody.remainsalmostconstant,varyingnotmorethan1°CRectalT:36.9-37.9°COralT:36.7-37.7°CAxillaryT:36.0-37.4°CRangeofBodyTemperatureFactorsaffectingnormaltemperatureCircadianrhythmIntheearlymorning,thebodyTisthelowest.Inlateafternoonorearlyevening,itisthehighest.AgeNewbornchild>adult>oldpersonSexWomen>man0.3°CMuscularactivityOtherfactors:emotion,eating,changeinclimateHeatProductionBMRofallthecellsExtrametabolismcausedbymuscleactivityhormone(thyroxine,growthhormoneandtestosterone)theeffectofepinephrine,norepinephrineandsympatheticstimulationonthecellsincreasedchemicalactivityinthecellsthemselvesHeatLoss

ThemajororgantolossheatistheskinBloodflowtotheskinfromthebodycoreprovidesheattransferMethodsofheatlossfromtheskintothesurroundingsEffectofEnvironmentairTemperatureonConductanceofHeatfromtheBody1)Insensibleperspiration2)SweatingInnervatedmainlybysympatheticcholinergicnerve(acetylcholine)CausedbynervousreflexMechanismofsweatsecretionPrimarysecretion

reabsorptionSweat(urea,lacticacid,K+)EvaporationRegulationofthebodytemperatureBehavioralcontrolofthebodytemperature

AutonomiccontrolofthebodytemperatureFeedbackmechanismsofregulationofthebodytemperatureTemperaturereceptorPeripheraltemperaturereceptorLocations:skin,mucous,,abdominalvisceraTypes:coldreceptorandwarmthreceptorcoldreceptor>warmthreceptorCentraltemperaturereceptorLocations:spinalcord,preopticandanteriorhypothalamicareaofthehypothalamus(PO/AH)Types:heat-sensitiveneuronsandcold-sensitiveneuronsTemperature-regulatingcenter1)Thethermoregulatingcenterismainlyinthehypothalamus2)ThePO/AHareaisthebasicthermostatictemperaturecontrollingcenterFeedbackmechanismsofregulationofthebodytemperatureEfferentpathways:ControloftheheatlossandheatproductionControloftheskinvasculartoneandsweatingbysympatheticnervesystemChangesofthemusculartensionbysomaticmotornervesystemControlofthemetabolicratebyalteringthefunctionofendocrinesystem,mainlythehormonesecretionofthethyroidglandsoradrenalmedulla“Set-point”

37°CPO/AHareaT>37°CProduction<lossT<37°CProduction>lossFeverIIIAutonomicNervousSystemReferenceAdinaMichael-Titus,etal.SystemoftheBody–TheNervousSystem.2ndversion,ElsevierLimited,2011.P24–28姚泰主编，8年制及7年制临床医学等专用生理学，第二版，人民卫生出版社，2010年。P478–482Section1.BasicoftheANSIncludingparasympatheticsympatheticentericdivisionsCoordinatescardiovascular,respiratory,digestive,excretoryandreproductivesystemsTheentericsystemanindependentnervoussystemresponsibleforregulationofdigestivefunctions.SomaticandAutonomicNervousSystemSomaticandAutonomicNervousSystemSomaticSkeletalmuscleConsciousandunconsciousmovementSkeletalmusclecontractsOnesynapseAcetylcholineAutonomicSmoothandcardiacmuscleandglandsUnconsciousregulationTargettissuesstimulatedorinhibitedTwosynapsesAcetycholinebypreganglionicneuronsandAChornorepinephrinebypostganglionicneuronsPreganglioniccellbodiesinlateralhornsofspinalcordT1-L2SympatheticDivisionParasympatheticDivisionPreganglioniccellbodiesinnucleiofbrainstemorlateralpartsofspinalcordgraymatterfromS2-S4PreganglionicaxonsfrombrainpasstogangliathroughcranialnervesPreganglionic

axonsfromsacralregionpassthroughpelvicnervestogangliaPreganglionicaxonspasstoterminalgangliawithinwallofornearorganinnervatedParasympatheticandsympatheticnervedistribution2.NeurotransmittersandNeuroreceptorsAcetylcholineandNorepinephrineAllpreganglionicneuronsarecholinergicParasympatheticpostganglionicneuronsarecholinergicSympatheticpostganglionicneuronsareadrenergicexceptSympatheticsinnervatingsweatglands,bloodvesselsinskeletalmuscle,andpiloerectionmusclesarecholinergicNeurotransmittersAChAChSweatglandsStriatedmuscleAChSOMATICNERVOUSSYSTEMHeartSm.mus.GlandsAChAChParasympatheticAChE,NEAd.M.

HeartSm.mus.GlandsAChNEAUTONOMICNERVOUSSYSTEMSympatheticSection3FunctionoftheSympatheticandParasympatheticNerveSNSSympatheticnervoussystemprototypically“fight”or“flight”.Associatedwithincreasedenergyexpenditurecardiopulmonaryadjustmentsforintenseactivity,bloodflowadjustmentsformaximumenergyexpenditure.SNS-Fight&FlightReactionYou’rewalkingaloneatnightandallthesuddenyouhearanunfamiliarnoisenearby…Inamatterofseconds,yourhea