Dual Action of iNOS-derived Nitric Oxide in Allergen-induced Airway Hyperreactivity In Conscious, Unrestrained Guinea Pigs

摘要

Using a guinea pig model of acute allergic asthma, we recently established that a deficiency of nitric oxide(NO) contributes to airway hyperreactivity (AHR) after the early asthmatic reaction(EAR) and that restoration of NO activity may contribute to the (Partial) reversal of AHR after the late asthmatic reaction(LAR). In the present study, we investigated the role of iNOS-derived NO in the regulation of AHR to histamine after the LAR. Inhalation of a selective dose of the specific iNOS inhibitor ami- Noguanidine(0.1 mM, 3 min) had no effect on basal airway reactivity to histamine in unchallenged, Ovalbumin-sensitized animals and did not affect the allergen-induced AHR after the EAR.