title: Influence of baclofen on laryngeal and spinal motor drive during cough in the anesthetized cat.
abstract: OBJECTIVE
  The antitussive properties of (±) baclofen on laryngeal muscle activities have not been determined. The hypothesis of this study was that administration of (±) baclofen would suppress upper airway muscle motor activity in a dose-dependent manner during cough.
  
  
  METHODS
  This is a prospective, preclinical, hypothesis-driven, paired design.
  
  
  METHODS
  Electromyograms of the parasternal, rectus abdominis, thyroarytenoid, posterior cricoarytenoid, and thyrohyoid were measured, along with esophageal pressure. Cough was elicited by mechanical stimulation of the lumen of the intrathoracic trachea in spontaneously breathing cats.
  
  
  RESULTS
  Baclofen (±) (3-10 μg kg(-1) i.a.) induced decreases in the electromyogram amplitude of the rectus abdominis motor drive during coughing, the inspiratory and active expiratory (E1) phases of cough, and cough number per epoch. There was no effect of (±) baclofen on the EMG amplitudes of any of the laryngeal muscles, the parasternal, or the duration of the passive expiratory (E2) phase.
  
  
  CONCLUSIONS
  Results from the present study indicate differential control mechanisms for laryngeal and inspiratory motor drive during cough, providing evidence of a control system regulating laryngeal activity and inspiratory spinal drive that is divergent from the control of expiratory spinal motoneurons.
authors.affiliation: Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida, U.S.A.
authors.forename: Daniel
authors.initials: D
authors.lastname: Castillo
authors.forename: Teresa
authors.initials: T
authors.lastname: Pitts
mesh_terms: D000818:Animals; D001418:Baclofen / Q000008:administration & dosage*; D002415:Cats; D003371:Cough / Q000188:drug therapy* / Q000503:physiopathology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004576:Electromyography; D005500:Follow-Up Studies; D007821:Laryngeal Muscles / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009125:Muscle Relaxants, Central / Q000008:administration & dosage; D011446:Prospective Studies
chemical_list: D009125:Muscle Relaxants, Central; D001418:Baclofen
keywords: Cough; antitussive; baclofen; larynx; parasternal; posterior cricoid arytenoid; rectus abdominis; thyroarytenoid; thyrohyoid; upper airway