title: Increases in airway responsiveness to histamine precede allergen-induced late asthmatic responses.
abstract: Changes in airway responsiveness to histamine after allergen inhalation challenge were studied in 14 nonsmoking atopic adult subjects with asthma. Inhalation challenges with allergen and with phosphate-buffered saline (control challenge) were performed single blind in random order, with an interval of 14 days. The development of a late asthmatic response was accompanied by an increase in airway histamine responsiveness that was significant when it was compared with the airway histamine responsiveness after the control challenge at 3 hours (p less than 0.01), 24 hours (p less than 0.01), and 48 hours (p less than 0.02), with recovery at 2 weeks after allergen inhalation. The 3-hour changes in airway responsiveness occurred independently of changes in airway caliber and correlated with the magnitude of the subsequent late response (r = 0.86; p less than 0.001). These results suggest that the tissue events (possibly airway inflammation) that underlie the late asthmatic response may occur before this response becomes clinically apparent.
authors.affiliation: Osler Chest Unit, Churchill Hospital, Oxford, England.
authors.forename: S R
authors.initials: SR
authors.lastname: Durham
authors.forename: C F
authors.initials: CF
authors.lastname: Craddock
authors.forename: W O
authors.initials: WO
authors.lastname: Cookson
authors.forename: M K
authors.initials: MK
authors.lastname: Benson
mesh_terms: D000328:Adult; D000485:Allergens; D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D004305:Dose-Response Relationship, Drug; D005260:Female; D005541:Forced Expiratory Volume; D006632:Histamine; D006801:Humans; D008297:Male; D011897:Random Allocation; D013997:Time Factors
chemical_list: D000485:Allergens; D006632:Histamine