Effects of antiallergic agents including levocabastine on experimental rhinitis in rats

Topical application of levocabastine hydrochloride (-)-[3S-[1(cis)-3 alpha,4 beta]]-1-[4-cyano-4-(4-fluorophenyl) cyclohexyl]-3-methyl-4-phenyl-4-piperidinecarboxylic acid monohydrochloride, inhibited the increase in dye leakage into the nasal cavity induced not only by antigen in actively sensitized rats but also by histamine in non-sensitized rats. The potency of levocabastine was stronger than that of ketotifen in inhibiting the increase of dye leakage in both cases. In addition, levocabastine as well as ketotifen exerted a more potent inhibition of the dye leakage induced by histamine than that induced by antigen. Levocabastine also exerted a significant inhibition on the dye leakage induced by substance P; again the effect of levocabastine was more potent than that of ketotifen. On the other hand, levocabastine elicited no remarkable influence on the dye leakage induced by either acetylcholine or platelet activating factor. However, ipratropium and (RS)-2-methoxy-3-(octadecylcarbamoyloxy)propyl 2-(3-thiazolio)ethyl phosphate were effective when the corresponding agonists were perfused, respectively.