O3-induced mucosa-linked airway muscle hyperresponsiveness in the guinea pig.

摘要: We investigated the effects of ozone exposure (3.0 ppm, 2 h) on responsiveness guinea pig airway muscle in vitro from animals developing bronchial hyperreactivity. Muscarinic reactivity vivo was determined by measuring specific resistance (sRaw) response to increasing concentrations aerosolized acetylcholine (ACh) administered before and 30 min after exposure. Immediately testing, multiple tracheal rings ozone- air-exposed were prepared contractile responses substance P, ACh, or KCl assessed presence 10 microM indomethacin with without 1 phosphoramidon, an inhibitor neutral endopeptidase. Isometric force generation measured stimulation cumulative agonists, (in g/cm2) calculated determination cross-sectional area. The smooth mucosa-intact airways pigs ozone-induced hyper-reactivity proved be hyperresponsive P ACh but not KCl. Pretreatment phosphoramidon abolished increase had no effect muscarinic hyperresponsiveness Furthermore, augmented ozone-exposed which mucosa been removed testing vitro. Likewise, present mucosa. Our data indicate that is increased hyperreactivity suggest this may linked non-cyclooxygenase mucosa-derived factors.