WELCOMETOHumanPhysiology(LECTURESESSION)Department of PhysiologyYangzhou University School of MedicineSpring2020
WELCOME TO Human Physiology (LECTURE SESSION) Department of Physiology Yangzhou University School of Medicine Spring 2020
CardiacMuscle CellsSkeletalCardiacmusclecellStriatedMuscleSkeletal musclecellSmoothmusclecellSmooth
Muscle Cells
Three Types of Muscle Cells1. Skeletalo Isattached toboneso itisstriatedo Is under voluntary controlMusclecells(fibers)aremultinucleated2. Smootho Is located in the walls of hollow internal structureso Is nonstriatedo Is under involuntary control3. Cardiaco It forms most ofthe hearto It is striated Itisunderinvoluntarycontrolo Itisautorhythmic
Three Types of Muscle Cells
NeuromuscularJunctionSNeuromuscularJunction
Neuromuscular Junction
NeuronmuscularJunctionTheNeuromuscularJunctionTerminalButtonAxonofmotorneuron1.MotorneuronactionpotentialarivesMuscleFibersattheaxonterminalActionpotenitialMyelinsheath2.Ca2+entersvoltage-gatedchannelsAxonTerminak3.Acetylcholinereleasefromvesiclestojunctional cleft4.AcetylcholinebindstoitsreceptorsonAxonterminalTerminalbuttomotorendplateVoltage-gated calciumchannelVesicleofacetylcholineActionpotenitial5.Natentersmusclefibers (musclecells)propagationVoltage-gated Na+ channelin.muscle.fiber营an6.End-platepotentialeachsthreshholdtofireactionpotertialonmusclecellmembranePiasmamembraneMuscle fiber7.DegradationofacetylcholinebyofmusclefiberacetylcholinesteraseAcetyicholine receptor siteXAcetylcholinesteraseNeurotransmitter-gated channelMotorend plate
Neuronmuscular Junction