title: Role of COX-2 in cough reflex sensitivity to inhaled capsaicin in patients with sinobronchial syndrome.
abstract: BACKGROUND
  Sinobronchial syndrome is a cause of chronic productive cough. Inflammatory mediators are involved in the pathophysiology of chronic productive cough. Accumulating evidences indicate that cyclooxygenase (COX)-2, one of the inducible isoforms of COX, is a key element in the pathophysiological process of a number of inflammatory disorders. However, little is known about the role of COX-2 in chronic productive cough in patients with sinobronchial syndrome known as neutrophilic bronchial inflammation.
  
  
  METHODS
  The effect of etodolac, a potent COX-2 inhibitor, on cough response to inhaled capsaicin was examined in 15 patients with sinobronchial syndrome in a randomized, placebo-controlled cross-over study. Capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting five or more coughs, was measured as an index of airway cough reflex sensitivity.
  
  
  RESULTS
  The cough threshold was significantly (p < 0.03) increased after two-week treatment with etodolac (200 mg twice a day orally) compared with placebo [37.5 (GSEM 1.3) vs. 27.2 (GSEM 1.3) muM].
  
  
  CONCLUSIONS
  These findings indicate that COX-2 may be a possible modulator augmenting airway cough reflex sensitivity in patients with sinobronchial syndrome.
authors.affiliation: The Department of Internal Medicine, Toyama City Hospital, Toyama, Japan. ishiura-@p2322.nsk.ne.jp.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Ishiura
authors.forename: Masaki
authors.initials: M
authors.lastname: Fujimura
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Ohkura
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Myou