title: Novel antitussive effect of suplatast tosilate in guinea pigs.
abstract: We studied the antitussive effects of suplatast, a Th2 cytokine inhibitor, and compared them with the effects of codeine using an experimental cough model in guinea pigs. Suplatast and codeine dose-dependently inhibited cough caused by mechanical stimulation of the larynx, but they did not inhibit cough caused by mechanical stimulation of the bifurcation of the trachea. In guinea pigs with bronchitis, suplatast had an antitussive effect on cough caused by stimulation of the larynx, whereas codeine did not inhibit such cough. In SO2-exposed guinea pigs, suplatast tended to inhibit cough caused by mechanical stimulation of the tracheal bifurcation. Further, suplatast inhibited citric acid-induced cough augmented by pretreatment with an angiotensin-converting enzyme inhibitor, whereas codeine did not inhibit such cough. Suplatast also inhibited bradykinin-induced discharges of airway vagal afferent nerves and significantly inhibited 4-aminopyridine-induced discharges of airway vagal afferent nerves. These findings indicate that the antitussive effects of suplatast are mediated by a novel mechanism involving the peripheral nervous system.
authors.affiliation: Laboratory of Presymptomatic Medical Pharmacology, Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto, Japan.
authors.forename: Jian-Rong
authors.initials: JR
authors.lastname: Zhou
authors.forename: Ryo-ichi
authors.initials: R
authors.lastname: Syono
authors.forename: Syu-ichi
authors.initials: S
authors.lastname: Fukumi
authors.forename: Kenji
authors.initials: K
authors.lastname: Kimoto
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Shirasaki
authors.forename: Fumio
authors.initials: F
authors.lastname: Soeda
authors.forename: Kazuo
authors.initials: K
authors.lastname: Takahama
mesh_terms: D015761:4-Aminopyridine / Q000494:pharmacology; D000818:Animals; D000996:Antitussive Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001190:Arylsulfonates / Q000494:pharmacology / Q000627:therapeutic use*; D001920:Bradykinin / Q000494:pharmacology; D001991:Bronchitis / Q000188:drug therapy* / Q000503:physiopathology; D003371:Cough / Q000188:drug therapy* / Q000503:physiopathology; D006168:Guinea Pigs; D008297:Male; D026902:Potassium Channel Blockers / Q000494:pharmacology; D012137:Respiratory System / Q000294:innervation; D013452:Sulfonium Compounds / Q000494:pharmacology / Q000627:therapeutic use*; D014630:Vagus Nerve / Q000187:drug effects / Q000502:physiology
chemical_list: D000996:Antitussive Agents; D001190:Arylsulfonates; D026902:Potassium Channel Blockers; D013452:Sulfonium Compounds; D015761:4-Aminopyridine; C073028:suplatast tosilate; D001920:Bradykinin