Abstract: Objective To observe the effect of several antihistamines, including epinastine, on the release of leukotriene B4 （LTB4）, interleukin 4 （IL-4） and interleukin 5 （IL-5） from spleen lymphocytes of allergic mice challenged by ovalbumin （OVA）. Methods OVA-sensitized BALB/c mice were used as animal model of allergy. Spleen lymphocytes isolated from these mice were treated with epinastine （0.1, 1.0, 10 μmol/L）, ebastine （10 μmol/L）, cetirizine （10 μmol/L）, and dexamethasone （1.0 μmol/L）, respectively, followed by incubation with OVA. Those cells without pretreatment with antihistamines served as the control. One hour after the challenge, enzyme-linked immunosorbent assay （ELISA） was applied to measure the level of LTB4, IL-4 and IL-5 in the cell culture supernates. Results Following the incubation with OVA, the levels of LTB4, IL-4 and IL-5 increased significantly in culture supernates of control spleen lymphocytes. Epinastine significantly inhibited the release of LTB4, IL-4 and IL-5 in a dose-dependent manner. At the concentration of 10 μmol/L, the inhibitory effect of epinastine was more potent than that of ebastine and cetirizine for IL-5 and LTB4 release （all P < 0.05）; for IL-4, the effect of epinastine was similar to that of ebastine （P > 0.05） but more potent than that of cetirizine （P < 0.05）. Conclusion Epinastine has a potent anti-inflammatory effect.

Key words: leukotriene B4, epinastine