title: Recovery time course of airway hyperresponsiveness to acetylcholine after ovalbumin challenge in guinea pigs.
abstract: Sequential changes in airway and adrenergic responsiveness after ovalbumin (OA) challenge were studied in guinea pigs. Airway responsiveness, alpha 1- and beta-adrenoceptor numbers and adenylate cyclase activity was determined after increasing doses of acetylcholine aerosol were administered before, 0, 3, 7, and 14 days after exposure to 2 percent OA or physiologic saline solution for 10 consecutive days. The antiasthmatic agent, azelastine (1 mg/kg/day, intraperitoneal), was administered for 14 days after the tenth exposure to OA in some animals. Airway responsiveness increased significantly after OA exposure, beta-adrenoceptor numbers decreased by 35 percent, and adenylate cyclase activity decreased by 54 percent (p less than 0.01). Values remained significantly different than control animals for 7 days and required 14 days to normalize completely. Azelastine decreased the recovery period to seven days. Azelastine may affect airway responsiveness, at least in part, by increasing beta-adrenergic responsiveness.
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, University of Nagoya, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Shindoh
authors.forename: S
authors.initials: S
authors.lastname: Sugiyama
authors.forename: K
authors.initials: K
authors.lastname: Takagi
authors.forename: T
authors.initials: T
authors.lastname: Satake
authors.forename: T
authors.initials: T
authors.lastname: Ozawa
mesh_terms: D000109:Acetylcholine; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction / Q000187:drug effects / Q000502:physiology*; D001993:Bronchodilator Agents / Q000494:pharmacology; D006168:Guinea Pigs; D008297:Male; D010047:Ovalbumin / Q000276:immunology*; D010793:Phthalazines / Q000494:pharmacology; D011941:Receptors, Adrenergic / Q000032:analysis / Q000502:physiology*; D013997:Time Factors
chemical_list: D001993:Bronchodilator Agents; D010793:Phthalazines; D011941:Receptors, Adrenergic; D010047:Ovalbumin; D000262:Adenylyl Cyclases; D000109:Acetylcholine; C020976:azelastine