title: Role of airway receptors in altitude-induced dyspnea.
abstract: OBJECTIVE
  The purpose of this study was to examine the role of airway receptors in respiratory-related sensations after ascent to altitude.
  
  
  METHODS
  Ratings of respiratory-related sensations, perceived exertion and acute mountain sickness, heart rate, and peripheral oxygen saturation were recorded at rest and exercise in male and female subjects who had inhaled either aerosolized saline or saline with tetracaine after acute ascent to an altitude of 3500 m and after prolonged acclimatization of 18 d at altitudes between 4000 and 5000 m.
  
  
  RESULTS
  Tetracaine had no effect on respiratory-related sensations at altitude either at rest or during exercise, and male and female subjects experienced similar respiratory-related sensations. Sensations of rapid breathing were experienced at rest after acute exposure to 3500 m as compared with sea level, but not after acclimatization to 5000 m. Sensations of rapid breathing, air hunger, and heavy breathing were experienced during exercise after acute and prolonged altitude exposure as compared with sea level, with a sensation of chest tightness experienced at 3500 m and a sensation of gasping experienced at 5000 m.
  
  
  CONCLUSIONS
  These results suggest that airway afferents play no role in the respiratory-related sensations experienced by male and female subjects either during acute ascent to altitude or after prolonged acclimatization at altitude.
authors.affiliation: Physical Therapy Department, School of Pharmacy and Health Sciences, University of the Pacific, Stockton, CA 95211, USA. jmansoor@uop.edu
authors.forename: J K
authors.initials: JK
authors.lastname: Mansoor
authors.forename: M W
authors.initials: MW
authors.lastname: Eldridge
authors.forename: K Y
authors.initials: KY
authors.lastname: Yoneda
authors.forename: E S
authors.initials: ES
authors.lastname: Schelegle
authors.forename: S C
authors.initials: SC
authors.lastname: Wood
mesh_terms: D000328:Adult; D000532:Altitude Sickness / Q000503:physiopathology*; D004417:Dyspnea / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D010100:Oxygen / Q000097:blood; D010465:Perception; D012143:Respiratory Physiological Phenomena; D012137:Respiratory System / Q000294:innervation*; D012737:Sex Factors; D013748:Tetracaine / Q000494:pharmacology
chemical_list: D013748:Tetracaine; D010100:Oxygen