Antigen-induced bronchospasm is associated with an impairment of airway mucociliary clearance, but the duration of this defect has not been examined. In the present study, we determined the time course of mucociliary dysfunction following inhalation challenge with Ascaris suum extract in conscious sheep with hypersensitivity to this antigen. Tracheal mucous velocity (TMV) as an index of mucociliary function, pulmonary resistance (RL), and arterial oxygen tension (PA(O)2) were measured prior to, immediately after, and serially for 8 h after inhalation challenge. TMV and PA(O)2 were then measured periodically for at least 2 wk. Immediately after A. suum challenge, mean RL increased to 264% of base line (P < 0.05), and mean PA(O)2 decreased to 61% of base line (P < 0.05). By 2 h postchallenge, mean RL and PA(O)2 had returned to base line but mean TMV had fallen to 61% of base line (P < 0.05). Mean TMV reached a minimum of 35% of base line after 5 h (P < 0.05) and remained significantly depressed between 37% and 54% of base line for 7 days; by day 9, mean TMV had returned to base line. Inhalation challenge with a control antigen (ragweed) failed to alter mean TMV, RL and PA(O)2 during the first 8 h and TMV and PA(O)2 at any time throughout the 2-wk observation period. We conclude that in allergic sheep 1) inhalation challenge with the specific antigen causes an impairment of mucociliary function that persists for several days, and 2) this impairment is not directly related to alterations in airway function.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Applied Physiology Respiratory Environmental and Exercise Physiology|
|State||Published - 1983|
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