Atopic cough-like cough hypersensitivity caused by active sensitization with protein fraction of Aspergillus restrictus strain A-17.
We examined the sensitivity of the cough reflex to inhaled citric acid in guinea pigs that had been actively sensitized with the protein fraction of Aspergillus restrictus strain A-17. The number of coughs elicited by an aerosol of 5% citric acid was significantly increased in the sensitized group compared to the non-sensitized group. The number of citric-acid-induced coughs in sensitized guinea pigs was dose-dependently and significantly reduced to the level in non-sensitized guinea pigs when animals were pretreated with fexofenadine, a selective histamine H1 receptor antagonist, 60min before citric acid inhalation. The bronchial responsiveness to inhaled methacholine or histamine in the sensitized group was not significantly heightened compared to the non-sensitized group. These results suggest that active sensitization with the protein fraction of A. restrictus by itself, that is without subsequent allergen challenge, enhances the excitability of cough receptors to tussive stimuli, and the physiologic features of this animal model are consistent with those of atopic cough.
Kamei
Junzo
J
Department of Pathophysiology and Therapeutics, Faculty of Pharmaceutical Sciences, Hoshi University, Tokyo 142-8501, Japan. kamei@hoshi.ac.jp
Takahashi
Yoshiki
Y
Itabashi
Takeshi
T
Hayashi
Shunsuke
S
Kawai
Ken-ichi
K
D000280:Administration, Inhalation; D000818:Animals; D000946:Antigens, Fungal / Q000276:immunology*; D000996:Antitussive Agents / Q000008:administration & dosage / Q000494:pharmacology; D001230:Aspergillus / Q000276:immunology*; D016535:Bronchial Hyperreactivity / Q000139:chemically induced / Q000276:immunology / Q000503:physiopathology; D016085:Bronchoconstrictor Agents / Q000008:administration & dosage / Q000494:pharmacology; D019343:Citric Acid; D003371:Cough / Q000139:chemically induced / Q000276:immunology* / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D005656:Fungal Proteins / Q000276:immunology*; D006168:Guinea Pigs; D006632:Histamine / Q000008:administration & dosage / Q000494:pharmacology; D017442:Histamine Agonists / Q000008:administration & dosage / Q000494:pharmacology; D039563:Histamine H1 Antagonists, Non-Sedating / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage / Q000494:pharmacology; D012130:Respiratory Hypersensitivity / Q000139:chemically induced / Q000276:immunology* / Q000503:physiopathology; D016593:Terfenadine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology
D000946:Antigens, Fungal; D000996:Antitussive Agents; D016085:Bronchoconstrictor Agents; D005656:Fungal Proteins; D017442:Histamine Agonists; D039563:Histamine H1 Antagonists, Non-Sedating; D016210:Methacholine Chloride; D019343:Citric Acid; D016593:Terfenadine; D006632:Histamine; C093230:fexofenadine