扬州大学：《生理学》课程教学课件（讲稿）第四章 心血管生理 Cardiovascular system Section 1 Pumping function of the heart

CardiovascularSystematriumHua DaiL.ventricleR.atriumMedicalSchoolR.ventricleYangzhou UniversityCardiovascularPhysiology

Cardiovascular System Hua Dai Medical School Yangzhou University Cardiovascular Physiology

System OverviewComponents of the cardiovascular system:.Heart.Vascular systemLatrium·BloodL.ventricleR.atriumR.ventricleCardiovascularsystem

System Overview  •Heart  •Vascular system  •Blood  Components of the cardiovascular system: Cardiovascular system

FlowatrestOrganml/minThe distribution of blood in aBrain650（13%)comfortable,resting personHeart215(4%)is shown here.Skeletal1030(20%)muscleDynamic adjustments in bloodSkin430(9%)delivery allow aperson toKidney950(20%)respond to widely varyingcircumstances, includingAbdominalemergencies.1200(24%)organsOther525（10%)Total5000（100%)Adapted trom Chapman and Mitchel

Dynamic adjustments in blood delivery allow a person to respond to widely varying circumstances, including emergencies. The distribution of blood in a comfortable, resting person is shown here

The heart is the pump that propels the bloodthrough the systemic and pulmonary circuits.Left side: Pumping bloodto systemic circulationL.atriumLventricleR.atriumRight side: Pumping bloodR.ventricletopulmonarycirculationCardiovascularsystem

Left side：Pumping blood to systemic circulation Cardiovascular system Right side：Pumping blood to pulmonary circulation The heart is the pump that propels the blood through the systemic and pulmonary circuits

Copyright @TheMcGraw-Hill Companies,Inc.Permissionrequired forreproductionordisplayTABLE12-1The Cardiovascular SystemCOMPONENTFUNCTIONHeartAtriaChambersthroughwhichblood flows fromveinsto ventricles.Atrial contraction adds toventricularfillingbutisnot essentialforit.VentriclesChambers whose contractionsproducethepressuresthatdrivebloodthroughthepulmonary and systemicvascularsystemsandbacktotheheartVascularsystemArteriesLow-resistancetubesconductingbloodtothevariousorganswithlittlelossinpressure.Theyalsoactaspressurereservoirsformaintainingbloodflowduringventricularrelaxation.ArteriolesMajorsitesofresistancetoflow,responsibleforthepatternofbloodflowdistributiontothevarious organs;participateintheregulationofarterial bloodpressureCapillariesSitesofnutrient,metabolicendproductandfluidexchangebetweenbloodandtissues.VenulesSitesofnutrient,metabolicendproduct,andfluidexchangebetweenbloodandtissues.VeinsLow-resistance conduits forblood flowback totheheart.Their capacityforblood is adjustedtofacilitatethisflow.BloodPlasmaLiquidportion ofbloodthatcontainsdissolved nutrients,ions,wastes,gases,andothersubstances.ItscompositionequilibrateswiththatofinterstitialfluidatthecapillariesCellsIncludeserythrocytesthatfunctionmainlyingastransport,leukocytesthatfunction inimmunedefenses,andplatelets(cellfragments)forbloodclotting

Chapter4CardiovascularsystemSection 1 Pumping function of the heartSection2 ElectrophysiologicalpropertySection3 VascularsystemSection4 Regulation of the heart

Chapter 4 Cardiovascular system Section 2 Electrophysiological property Section 1 Pumping function of the heart Section 3 Vascular system Section 4 Regulation of the heart

What happens in the heart during eachcardiac cycle?CORRELATIONOFEVENTSINLEFTSIDEOFHEARTELECTROCAROIOGRAM·PressurePRESSURE mmHg120.VolumeLentAtrial8PressureDENTRICULARUOLUME.Valves120· Blood flowD-Ventricular diastole S-Ventricular systole

What happens in the heart during each cardiac cycle? • Pressure • Volume • Valves • Blood flow

The major external and internal parts of the heartare shown in this diagram.Copyright@The MctwoaArteriestoheadandarmAortaRight pulmonarLeft pulmonaryRightpulmonaryveirarterySuperior vena cavLeft pulmonaryveinsPulmonary trunkInteratrial septuLeftatriumLett (bicuspid)AVvalveRight atriumAortic semilunarvalveRightAV(tricuspid) valvLeft ventriclePapilary muscleInferiorvena cavInterventricularseptuChordae tendiMyocardiumRightventricEpicardiumPericardial fluid/spacePericardiumPumonanhilunar valveThe black arrows indicate the route taken by theblood as it is pumped along

The black arrows indicate the route taken by the blood as it is pumped along. The major external and internal parts of the heart are shown in this diagram

Cardiac cycleThe cardiac events that occur from beginning of oneheartbeat to the beginning of the next are called thecardiac cycle.Time: T oc 1/f = 60 s/ 75 = 0.8 sVentricleAtriasystole: 0.3 ssystole: 0.1 sdiastole: 0.5 sdiastole: 0.7 s

The cardiac events that occur from beginning of one heartbeat to the beginning of the next are called the cardiac cycle. Cardiac cycle Time：T ∝ 1/f ＝ 60 s/ 75 ＝ 0.8 s Atria systole: 0.1 s diastole: 0.7 s Ventricle systole: 0.3 s diastole: 0.5 s

Cardiac Cycle : whole heart diastole has 0.4 s.VentriclescontractcontracAtriumsrelaxVentriclesrelaxand fill

Cardiac Cycle contract : whole heart diastole has 0.4 s