SpasmMuscle RelaxationMusclesMuscle, SkeletalMuscle, SmoothMuscle SpasticityNeck MusclesMuscle ContractionMuscle ProteinsMuscle, Smooth, VascularSpasms, InfantileMuscle Fibers, SkeletalCervical AtlasOccipital BoneElectromyographyMuscle DevelopmentElectric StimulationNeuromuscular AgentsLegSpinal Cord InjuriesMotor NeuronsMuscle FatigueHemifacial SpasmBotulinum Toxins, Type ARelaxation TherapyMuscle Fibers, Fast-TwitchMuscle DenervationMuscle Fibers, Slow-TwitchIsometric ContractionMyocytes, Smooth MuscleTime FactorsMitochondria, MuscleOculomotor MusclesFacial MusclesMuscle SpindlesMuscle, StriatedMuscular AtrophyPapillary MusclesRespiratory MusclesMuscle WeaknessCoronary VasospasmCalciumTracheaHindlimbNitric OxideRabbitsAbdominal MusclesAcetylcholineMuscle CellsQuadriceps MuscleVasodilationRats, Sprague-DawleyMasseter MuscleMasticatory MusclesIntermittent ClaudicationPhosphocreatineIntercostal MusclesEsophageal Spasm, DiffuseCattleCells, CulturedTissue AdhesionsPostoperative ComplicationsGuinea PigsDose-Response Relationship, DrugCyclic GMPRats, WistarBiomechanical PhenomenaSatellite Cells, Skeletal MuscleReflex, StretchRegional Blood FlowPeripheral Arterial DiseaseVasodilator AgentsNeuromuscular JunctionPectoralis MusclesPostoperative PeriodMuscular DiseasesNitroprussideDeuteroporphyrinsElectric Stimulation TherapyEndothelium, VascularNeuromuscular BlockadeMyofibrilsRNA, MessengerMuscle Relaxants, CentralNeuromuscular Nondepolarizing AgentsHSP20 Heat-Shock ProteinsCatsMagnetic Resonance ImagingPenisPsoas MusclesIsoproterenolExerciseAortaSignal TransductionMagnetic Resonance SpectroscopyTreatment OutcomeAnkleDogsTemporal MuscleKinetics