TracheaTracheal NeoplasmsTracheal DiseasesTracheal StenosisGuinea PigsMuscle, SmoothBronchiMuscle RelaxationLarynxIntubation, IntratrachealMuscle ContractionRespiratory SystemMucusTracheotomyBronchoscopyLungHistamineEpitheliumAirway ObstructionTracheitisSRS-AExocrine GlandsMethacholine CompoundsBronchial DiseasesNeurokinin ATracheostomyBronchial NeoplasmsSubstance PParasympatholyticsParasympathetic Nervous SystemVagus NerveTracheoesophageal FistulaLaryngeal NervesAtropineLaryngeal CartilagesAcetylcholineMucous MembraneTachykininsMucociliary ClearanceElectric StimulationFiber Optic TechnologyIsoproterenolAporphinesCapsaicinAirway ResistanceRespiratory MucosaCarbacholThyroid CartilageLaryngoscopyIndomethacin