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EnergyMetabolismBodyTemperatureSECTIONAEnergyMetabolismScience.Science.2009 Jul 10;2009 Jul 10;325(5937):201-4.325(5937):201-4.Caloric restriction delays disease onset and mortality in Caloric restriction delays disease onset and mortality in rhesus monkeys.rhesus monkeys.Colman RJ,Anderson RM,Johnson SC,Kastman EK,Kosmatka KJ,Beasley TM,Allison DB,Cruzen C,Simmons HA,Kemnitz JW,Weindruch R.Wisconsin National Primate Research Center,University of Wisconsin,Madison,WI 53715,USA.rcolmanprimate.wisc.eduCaloric restriction(CR),without malnutrition,delays aging and extends life span in diverse Caloric restriction(CR),without malnutrition,delays aging and extends life span in diverse species;however,its effect on resistance to illness and mortality in primates has not been species;however,its effect on resistance to illness and mortality in primates has not been clearly established.We report findings of a 20-year longitudinal adult-onset CR study in rhesus clearly established.We report findings of a 20-year longitudinal adult-onset CR study in rhesus monkeys aimed at filling this critical gap in aging research.In a population of rhesus macaques monkeys aimed at filling this critical gap in aging research.In a population of rhesus macaques maintained at the Wisconsin National Primate Research Center,moderate CR lowered the incidence of maintained at the Wisconsin National Primate Research Center,moderate CR lowered the incidence of aging-related deaths.At the time point reported,50%of control fed animals survived as compared aging-related deaths.At the time point reported,50%of control fed animals survived as compared with 80%of the CR animals.Furthermore,CR delayed the onset of age-associated pathologies.with 80%of the CR animals.Furthermore,CR delayed the onset of age-associated pathologies.Specifically,CR reduced the incidence of diabetes,cancer,cardiovascular disease,and brain Specifically,CR reduced the incidence of diabetes,cancer,cardiovascular disease,and brain atrophy.These data demonstrate that CR slows aging in a primate species.atrophy.These data demonstrate that CR slows aging in a primate species.美国一项研究表明,限制热量摄入,美国一项研究表明,限制热量摄入,提供适量营养,可以提供适量营养,可以推迟衰老,延长寿命推迟衰老,延长寿命。EnergymetabolismThermalequivalentoffood、Thermalequivalentofoxygen、RespiratoryQuotient(RQ),Non-proteinRQ(NPRQ)Factorsaffectingenergymetabolism Basal conditions,Basal conditions,BasalMetabolicRate,(BMR)MeasurementofthemetabolicrateKey wordsGeneral consideration1.Areviewofprincipalchemicalprocessesofthecell;2.Ananalysisoftheirphysiologicimplications,especiallythemannerinwhichtheyfitintotheoverallconceptofhomeostasis.Concept of energy metabolism:Theprocessesofliberation,transformation,storageandutilizationoftheenergyproducedbythematerialmetabolisminthebody.Source,transfer and storage of energy 1)Adenosinetriphosphate(ATP)functionsasan“energycurrency”inmetabolism.2)CP(phosphocreatine)functionsasanaccessorystoragedepotforenergyandasan“ATP buffer”Phosphocreatine+ADP=ATP+CreatineConcept of“free energy”lTheenergyinfoodscanbemadebythechemicalreactionsinthecellslTheenergyisavailabletothevariousphysiologicsystemsofthecells.lTheamountofenergyliberatedbycompletedoxidationofafoodiscalledthefree energy of oxidation of the food.RepresentedbythesymbolG.lATPisanessentiallinkbetweenenergy-utilizingandenergy-producingfunctionsofthebody.-theenergycurrencyofthebody.lEnergyderivedfromtheoxidationoffoodisusedtoconvertadenosinediphosphate(ADP)toATP.ATPisthenconsumedbythevariousreactionsofthebody.Role of“Adenosine Triphosphate(ATP)”in metabolismMetabolic rate lThemetabolismofthebodysimplymeansallthechemicalreactionsinallthecellsofthebody.lMetabolic rateisnormallyexpressedintermsoftherateofheatliberationduringchemicalreactions.Heatistheendproductofalmostalltheenergyreleasedinthebody.Measurement of the whole-body metabolic rate DirectCalorimetrytomeasurethesumofheatproductionofwholebodyinaunitoftimephysicallydifficulttoperformusedonlyforresearchpurposesIndirectCalorimetrytheprincipleofchemicalreactionstocheckuphowmuchcarbohydrates,fatsandproteinsareoxidizedrespectivelyincertaintimestocalculatethesumofheatproductionofbodyinthistimesC6H12O66O26CO26H2OH(Glucose)Measurement of the whole-body metabolic rate ThermalEquivalentofFoodCaloriesliberatedby1gramoffoodoxidizedinbody(orburnedoutofbody).biological thermal equivalent(oxidizedinbody)physical thermal equivalent(burnedoutofbody)ThermalEquivalentofOxygenIntheprocessofoxidizingfood,Caloriesliberatedperliteroxygen(O2)consumed.RespiratoryQuotient(RQ)Intheprocessofoxidizingfood,theratioofcarbondioxideproducedtooxygenusedCO2produced(ml)RQO2used(ml)Non-ProteinRespiratoryQuotient(NPRQ)Intheprocessofoxidizingthecarbohydratemixedwithfatindifferentproportion,theratioofcarbondioxideproducedtooxygenusedmental activitymuscletonusandreleasinghormonesmetabolicrateFactorsaffectingenergymetabolismmovement of musclesenhancesrateofmetabolismtemperature of environment Metabolicrateisthemoststableduring2030,riseorfallintemperatureenhancesthemetabolicrateingestion of food(specificdynamiceffectoffoods)BasalMetabolicRate(BMR)theenergymetabolismunder“basalconditions”basal conditions:morning,waking,lyingdownquietly,nomovement;hadagoodsleepthepreviousnight;atcompleterest,noise,discomfort,andemotionalimpactsaretobeavoided;12hoffooddeprivationatleast;environmentaltemperature2025。BasalMetabolicRate(BMR)Themetabolismsomeasuredincludesthefundamentalbasalmetabolismofallcellsandsomesteadyfunctionssuchasthoseofthekidney,heart,andrespiratorymuscles.BMRisexpressedasCaloriesperhourpersquaremeterofbodysurfacearea,calculatedfromheightandweight.Calories/m2/hourCalculation of basal metabolic rate Simplified method:e.g.RQis0.82,ThermalEquivalentofOxygenis20.18KJL(fromthetable),O2usedis15Lh(a20yearoldman,underbasalconditions),surfaceareaofbodyis1.5m2,(calculateaccordingtoheightandweight),SotheBMRis:20.18KJL15Lh1.5m2201.8KJ(m2h)ThenormalvalueofBMRofthe20yearoldmanis157.8KJ(m2h)(fromthetable),Sothemanvalueisoverthenormalvalue:(201.8157.8)157.8100%28%Significances of Change of BMR 1015%normalover20%abnormalBMRhyperthyroidism,fever,diabetes,spherocytosis,leukemia,andheartdiseaseswithdyspnea.BMRhypothyroidism,pathologicalhunger,Addisonsdisease,nephroticsyndrome,andpituitarigenicobesity,etcSectionBBodyTemperatureRegulationBodyTemperatureaverageinternaltemperatureinbodythe“core”ofthebody.coretemperatureshelltemperatureNormal body/core temperatureRectaltemperature:36.937.9Oraltemperature:36.737.7,lower than rectal lower than rectal 0.50.5Axillarytemperature:36.037.4,lower than oral lower than oral 0.30.3NormalChangeslCircadian rhythm,nomorethan1lSex:femalemaleabout0.3,menstruationlAge:infancymiddle-ageoldagelOthers:movement,stress,exciting,ingestionoffood,etc.Thermogenesis(heat production)sumofheatproduction=basalmetabolismspecificdynamiceffectoffoodsmovementofskeletalmusclesrest time:heatproducedmainlybythedeeporgans(liver)movement:heatproducedmainlybyskeletalmusclescold climate:heatproducedbymuscletonus,shivering,hormonessecretion(Epinephrine,Norepinephrine,Thyroxine)Thermolysis(heatloss)throughskin(97%),respiration(2%),urineandexcrement(1%)Heat loss by skin Radiation:temperaturedifferencebetweenskinandenvironment,effectiveradiationarea Conduction:temperaturedifferencebetweenskinandobject,toucharea,conductingheatdegreeofobject Convection:windspeed,flowspeed,temperaturedifferenceandeffectiveareaEvaporation:insensibleperspirationHeatislostbyevaporationofwaterexudedfromskinandrespiratorytract.sensibleperspiration(sweating)Heatislostbyevaporationofsweatsecretedbysweatgland.When:airtemperatureskintemperature,theevaporation isonlyonemeansofheatloss.AttentionSweatingprocessesandThermolysiswarmandhotenvironmentstimulatesskinthermoreceptorsandheatingbloodstreamsweatingcenter(mainlyinhypothalamus)sympatheticcholinergicfiberssmallsweatglandthermalsweatingSweatingspeedaffectedbyenvironmentaltemperature,humidity,windspeed,andmovementintensity,etc.mentalsweatingnosignificanceinthermoregulationEffectsofSkinBloodFlowonThermolysishot environmentdecreasethetonusofsympatheticnervoussystemarteriolesrelaxandarteriovenousanastomosesopenintheskinincreases theskinbloodflowskintemperaturerisesincreasestheheatlosscold environmentincreasethetonusofsympatheticnervoussystemarteriolescontractandarteriovenousanastomosescloseintheskinreducestheskinbloodflowskintemperaturefallsreducestheheatlossRegulation of body temperature Bodytemperatureiscontrolledbybalancingheat productionagainstheat loss.Behavioralthermoregulation:Humanbeingkeepsthebodytemperatureconstantthroughmanyconsciousactivities.Theregulatoryprocessofbodytemperatureperformedbyanintrinsicautonomicregulationmechanisminthebody.AutonomicthermoregulationAutonomicthermoregulationTheregulatoryprocessofbodytemperatureperformedbyanintrinsicautonomicregulationmechanisminthebody.ThermoreceptorsPeripheral Thermoreceptor:locatedintheskin,mucosa,andinternalorgans,coldreceptorandwarmthreceptor,bothofthemarethefree(unmyelinated)nervousterminals.Central Thermoreceptor:existinginspinalcord,medullaoblongata,reticularstructureinbrainstem,andhypothalamus;inwhich,preoptic anterior hypothalamus(PO/AH)containsheat-sensitiveneuronandcold-sensitiveneuronAfferentnerves(pathways):inperipheralafferentnerves,autonomicnervoussystemandcentralafferentfibers,bloodflowisoneofafferentpathways.ThermoregulationCenters:basiccenterinhypothalamus,anteriorhypothalamusisheatlosscenter,posteriorhypothalamusisheatproductioncenter,PO/AHareaisintegratedcenter.Efferentnerves(pathways):Motornervessystemtotheskeletalmuscles,Endocrinesystem:epinephrine,norepinephrine,thyrineSympatheticadrenergicnervefibersinnervatingvesselsinskinandmucosa,Sympatheticcholinergicnervefibersinnervatingsweatgland.Effectororgans:heatproductionliver,skeletalmuscles,etc;heatlossskinvessels,sweatgland.“set-point”theoryofthermoregulationtemperature-sensitiveneuronsinPO/AHareaexhibits“set-point”function,theset-pointisnormallysetin37.Attemperaturesabovethislevel,therateofheatlossisgreaterthanthatofheatproduction,sothatthebodytemperaturefallsandreapproachesthe37level.Attemperaturesbelowthislevel,therateofheatproductionisgreaterthanthatofheatloss,sothatthebodytemperaturerisesandagainapproachesthe37level.Behavioral control of body temperature Asidefromthesubconscious mechanismsforbodytemperaturecontrol,thebodysanothertemperature-controlmechanism,evenmorepotent.Whenevertheinternalbodytemperaturebecomestoo high,signalsfromthetemperature-controllingareasinthebraingivethepersonapsychicsensationofbeingoverheated.Conversely,wheneverthebodybecomestoo cold,signalsfromtheskinandprobablyalsofromsomedeepbodyreceptorselicitthefeelingofcold discomfort.therefore,thepersonmakesappropriateenvironmentaladjustmentstore-establishcomfort,suchasmoving into a heated roomorwearingwell-insulated clothinginfreezingweather.Abnormality of body temperature regulation-Fever Fever Bodytemperatureabovetheusualrangeofnormal.Causes:1.abnormalitiesinthebrainitselfortoxicsubstancesthataffectthetemperature-regulatingcenters2.include:bacterialdiseases,braintumors,andenvironmentalconditionsthatmayterminateinheatstroke.Theset-pointofthehypothalamicthermostatisresettoahighlevel.Themechanismsofheatproductionandheatlossarebalanced on this higher level.l请结合你所学的知识,分析该患者出现腹痛的生理学机制。请结合你所学的知识,分析该患者出现腹痛的生理学机制。Review lSubjectsofbestchoice:1.RQ(respiratoryquotient)is:A.Inthegivenperiodoftime,theratioofxygenusedtocarbondioxideproducedinthebody;B.Inthegivenperiodoftime,theratioofcarbondioxideproducedtooxygenusedinthebody;C.theratioofairexhaledtoairinhaledD.theratioofcarbondioxideproducedtoused2.RQ value is minimum in which one?lA.SugarlB.proteinlC.fatlD.vitaminlE.mineralsalt3.The specific dynamic effect is most powerful in which food lA.SugarlB.proteinlC.fatlD.vitaminlE.mixingfood4.In the view of physiology,body temperature is lA.oraltemperaturelB.rectaltemperaturelC.armpitaltemperaturelD.averageskintemperatureofthebodylE.averagecoretemperatureofthebodylA.spinalcordlB.medullaoblongatalC.reticularstructureofbrainstemlD.preopticanteriorhypothalamus(PO/AH)lE.cerebralcortex5.The set-point of temperature regulation center lies in 6.Most of the heat lost in the body is by:lA.respiratorytractlB.digestivetractlC.urinarytractlD.skinlE.pulmonarycirculation7.The basal metabolic rate(BMR)value is the most stable under the circumstance temperature between:lA.1014lB.1519lC.2030lD.3135lE.36408.The following relates about the basal metabolism,which one is wrong?lA.itismeasuredunder“basalconditions”lB.theaveragevaluesforchildarelargerthanfortheadultlC.Itreflectsthelowestlevelofenergymetabolismofthebody.lD.itisexpressedasarelativevalueincliniclE.thevalue1015%higherorlowerthannormalaveragevaluebelongtonormal9.The following relates about the normal change of body temperature,which one is right?lA.therangeofnormalchangeisirregular.lB.therangeofcircadianrhythmisover2lC.bodytemperatureislowerinafternoonthanthatinmorninglD.womansbodytemperaturedecreasesafterovulating.lE.thebodytemperatureincreasesduringmusclesactivity.10.BMR decreases in which one of the disease conditions following?lA.feverlB.hyperthyroidismlC.diabeteslD.spherocytosislE.Hypothyroidism11.BMR is the calories calculated by:lA.weightlB.heightlC.agelD.bodysurfacearealE.circumstancetemperature12.Which method is utilized when we sponge a fever patient with alcohol to decrease the body temperature?lA.radiationlB.conductionlC.convectionlD.insensibleevaporationlE.evaporation13.A malaria patient suddenly feels chilly and chills,the body temperature is 39.this change is caused by:lA.excitementofthermolysiscenterlB.inhibitionofthermogenesiscenterlC.theset-pointincreasedtoahighervaluelD.vasodilationofskinlE.functionalimpairmentoftemperatureregulation14.14.The body temperature of a pneumonia hyperpyrexia The body temperature of a pneumonia hyperpyrexia(肺炎高热肺炎高热)patient decline to normal after the application)patient decline to normal after the application of antibiotics.The following relates about the process of of antibiotics.The following relates about the process of temperature regulation,which one is wrong?temperature regulation,which one is wrong?lA.excitementofthermolysiscenterlB.inhibitionofthermogenesiscenterlC.theset-pointreturnstonormallevellD.vasodilationofskinlE.thefunctionalimpairmentoftemperatureregulationunderfebrileconditionrepairedtonormal15.At normal room temperature,in a resting person,body heat loss is mainly by which means?lA.radiationlB.conductionlC.convectionlD.insensibleevaporationlE.evaporation16.When the temperature of the surroundings is greater than that of skin,the body rid heat by which means?lA.radiationlB.conductionlC.convectionlD.insensibleevaporationlE.evaporation17.Treatment of hyperpyrexia patient with ice cap is mainly to increase:lA.heatlossbyradiationlB.heatlossbyconductionlC.heatlossbyconvectionlD.heatlossbyevaporationlE.sweating18.Wearing cotton clothes to drive cold is mainly to decrease:lA.heatlossbyradiationlB.heatlossbyconductionlC.heatlossbyconvectionlD.heatlossbyevaporationlE.sweatingMetabolismrateMeta
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