title: Laryngeal narrowing during nasal ventilation does not originate from bronchopulmonary C-fibers.
abstract: We previously showed that nasal pressure support ventilation (nPSV) can lead to active inspiratory laryngeal narrowing, which originates from the stimulation of bronchopulmonary receptors. Among the three major types of bronchopulmonary receptors, which are variably stimulated by lung distension, C-fiber endings are remarkable, given that their stimulation can also trigger laryngeal closure. Taking advantage of our lamb model with blocked C-fibers, we aimed to assess whether bronchopulmonary C-fiber endings are involved in the active inspiratory laryngeal narrowing during nPSV. Nine lambs were surgically instrumented to assess states of alertness, electrical activity of a glottal constrictor (EaTA), respiratory movements and arterial blood gases. Forty-eight hours later, two polysomnographic recordings were performed during nPSV 15/4 cmH2O, before and after C-fiber blockade. During nPSV, blockade of C-fibers did not prevent inspiratory EaTA (present for 74±41% of respiratory cycles vs. 64±35%, p=0.9). We conclude that active inspiratory laryngeal narrowing during nPSV does not originate from bronchopulmonary C-fiber endings.
authors: Neonatal Respiratory Research Unit, Departments of Pediatrics and Physiology, Université de Sherbrooke, QC, Canada J1H 5N4.
authors: Nathalie
authors: N
authors: Samson
authors: Neonatal Respiratory Research Unit, Departments of Pediatrics and Physiology, Université de Sherbrooke, QC, Canada J1H 5N4.
authors: Lalah
authors: L
authors: Niane
authors: Neonatal Respiratory Research Unit, Departments of Pediatrics and Physiology, Université de Sherbrooke, QC, Canada J1H 5N4.
authors: Stéphanie
authors: S
authors: Nault
authors: Neonatal Respiratory Research Unit, Departments of Pediatrics and Physiology, Université de Sherbrooke, QC, Canada J1H 5N4.
authors: Charlène
authors: C
authors: Nadeau
authors: Neonatal Respiratory Research Unit, Departments of Pediatrics and Physiology, Université de Sherbrooke, QC, Canada J1H 5N4. Electronic address: jean-paul.praud@usherbrooke.ca.
authors: Jean-Paul
authors: JP
authors: Praud
mesh_terms: D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D003679:Deglutition / Q000187:drug effects / Q000502:physiology; D018755:GABA Agonists / Q000494:pharmacology; D007539:Isonicotinic Acids / Q000494:pharmacology; D007821:Laryngeal Muscles / Q000502:physiology*; D007823:Laryngeal Nerves / Q000098:blood supply / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D009666:Nose / Q000502:physiology; D010812:Physical Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012121:Respiration, Artificial; D012129:Respiratory Function Tests; D014867:Water / Q000378:metabolism
chemical_list: D018755:GABA Agonists; D007539:Isonicotinic Acids; D014867:Water; C015300:isoguvacine
keywords: Capsaicin; Lamb; Nasal pressure support ventilation; Thyroarytenoid muscle