title: Effects of thromboxane A2 antagonist on airway hyperresponsiveness, exhaled nitric oxide, and induced sputum eosinophils in asthmatics.
abstract: We examined effects of a thromboxane A2 (TXA2) antagonist seratrodast on airway hyperresponsiveness, exhaled nitric oxide (NO), and eosinophils in induced sputum in 14 asthmatics. Subjects were administered 80 mg of seratrodast once a day for 4 weeks. Respiratory conductance (Grs) was measured by the forced oscillation method and airway responsiveness was evaluated as the inhaled dose of methacholine, which induced 35% decrease in Grs. Subjects breathed into a Teflon bag, and NO concentration in the bag was measured by a chemiluminescence analyzer. Induced sputum comprised the entire expectorate produced during a 20 min inhalation of 3% saline, and was analyzed for total and differential cell counts. Airway hyperresponsiveness was significantly decreased by seratrodast. By contrast, no differences in either exhaled NO or percentage of eosinophils in sputum were observed before or after seratrodast. We conclude that seratrodast may attenuate airway hyperresponsiveness, presumably by antagonizing TXA2 released from the inflamed airways.
authors.affiliation: Research Institute for Diseases of the Chest, Faculty of Medicine, Kyushu University, Fukuoka, Japan. aizawa@kokyu.med.kyushu-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Aizawa
authors.forename: H
authors.initials: H
authors.lastname: Inoue
authors.forename: H
authors.initials: H
authors.lastname: Nakano
authors.forename: K
authors.initials: K
authors.lastname: Matsumoto
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: S
authors.initials: S
authors.lastname: Fukuyama
authors.forename: H
authors.initials: H
authors.lastname: Koto
authors.forename: N
authors.initials: N
authors.lastname: Hara
mesh_terms: D018927:Anti-Asthmatic Agents / Q000494:pharmacology; D001249:Asthma / Q000378:metabolism*; D016227:Benzoquinones / Q000494:pharmacology*; D016535:Bronchial Hyperreactivity / Q000378:metabolism*; D004804:Eosinophils / Q000187:drug effects*; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006538:Heptanoic Acids / Q000494:pharmacology*; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D016210:Methacholine Chloride / Q000494:pharmacology; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D011448:Prostaglandin Antagonists / Q000494:pharmacology; D012119:Respiration; D013183:Sputum / Q000166:cytology; D013928:Thromboxane A2 / Q000037:antagonists & inhibitors*
chemical_list: D018927:Anti-Asthmatic Agents; D016227:Benzoquinones; D006538:Heptanoic Acids; D011448:Prostaglandin Antagonists; D016210:Methacholine Chloride; D009569:Nitric Oxide; C060230:seratrodast; D013928:Thromboxane A2