Abstract: Objective To investigate the anti-inflammatory properties of mizolastine and explore its possible mechanisms. Methods Edema at hind-paw of rat was induced by a single injection of arachidonic acid(AA), each containing 0.1 mL of prepared AA(0.3%). The intensity of AA-induced reactions was expressed as an increasing of rat paw thickness, which was measured by micrometer. After the drugs (mizolastine, loratadine, cetirizine) were given orally separately, the inhibitory effects were determined by the de-creasing of edema intensity. Zileuton and mizolastine were given orally separately and the inhibitory effects were compared subsequently. Results The intensity of AA-induced edema was significantly inhibited by mizolastine, but not by loratadine or cetirizine There was no significant difference between mizolastine and zileuton in the inhibition of AA-induced edema. Conclusion Mizolastine possesses anti-inflammatory properties in vivo, which may be related to the inhibition of the 5-lipogenase pathway.

Key words: Arachidonicate 5-lipoxygenase, Mizolastine, Models, animal