Oxidative stress appears to be relevant to asthma pathogenesis. Therefore, the effectiveness of the antioxidant N -acetylcysteine was examined on antigen-induced pulmonary responses in sensitized Brown-Norway rats. N -acetylcysteine (oral, 1 mmol kg(-1)per day for 7 days before challenge) did not reduce the immediate bronchospasm that followed aerosol antigen exposure but prevented airway hyperreactivity to 5-hydroxytryptamine at 24 h after antigen challenge, and reduced the eosinophils (from 0.178 +/- 0.038 in the absence to 0.064 +/- 0.020 x10(6)cells ml(-1)in the presence of N -acetylcysteine;P< 0.05), and Evans blue dye extravasation in bronchoalveolar lavage fluid. Taurine levels in bronchoalveolar lavage fluid from antigen-challenged rats were higher than control values but treatment with N -acetylcysteine failed to further increase these augmented levels. In conclusion, oral N -acetylcysteine showed beneficial effects in an in vivo model of experimental asthma, which confirm and extend the previous positive findings obtained in other models of lung injury.
Copyright 2002 Elsevier Science Ltd.