[Effect of KW-4679, an antiallergic drug, on antigen-induced airway microvascular leakage in rats passively sensitized with mouse monoclonal IgE antibody].

We studied the effect of KW-4679, an antiallergic drug, on inhaled antigen-induced airway microvascular leakage in rats passively sensitized with mouse monoclonal IgE antibody. Inhaled antigen increased extravasation of Evans blue dye content in tracheal and main bronchus tissues. KW-4679 (0.3-10 mg/kg, p.o.) reduced antigen-induced microvascular leakage in trachea with an ED40 value of 4.9 mg/kg. KW-4679 also reduced antigen-induced microvascular leakage in main bronchus with an ED40 value of 0.47 mg/kg. The inhibitory effect of KW-4679 was more potent than those of ketotifen and terfenadine. These results suggest that KW-4679 clearly reduces airway microvascular leakage mediated by antigen-antibody reaction.