Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma

摘要

BackgroundUsing guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC) nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO) production – due to competition with neuronal NO-synthase (nNOS) for the common substrate, L-arginine. Furthermore, in a guinea pig model of allergic asthma, airway arginase activity is markedly increased after the early asthmatic reaction (EAR), leading to deficiency of agonist-induced, epithelium-derived NO and subsequent airway hyperreactivity.In this study, we investigated whether increased arginase activity after the EAR affects iNANC nerve-derived NO production and airway smooth muscle relaxation.