Abstract: AIM: To study the therapeusis of arsenic trioxide on asthma and the effects of arsenic on T cell cycle and Bcl-2 expression in asthmatic mice.METHODS: 49 healthy Kunming male mice at 5 wk of age were randomly divided into 7 groups:control group, asthmatic group, dexamethasone group and arsenic group (the mice were given arsenic trioxide 0.575, 1.15, 2.3, and 4.6 mg·kg^-1 before challenge).An animal model of asthma was established by means of OVA sensitizing-challenging.Pulmonary functions in those mice were measured by Organism Signal Collection System software.Total leucocytes and its cell classification, protein concentrations, and pulmonary function were detected.CD3 expression, T cell cycle and Bcl-2 expression were detected by flow cytometry.RESULTS: In those groups treated with arsenic trioxide, compared with asthmatic group, the pulmonary function improved, the count of total leucocytes, eosinophils, lymphocytes and protein concentrations decreased.There were double effects of arsenic trioxide on T cell in spleen: induction apotosis in the dose of 1.15 mg·kg^-1, inhibition proliferation and activation in the dose of 4.6 mg·kg^-1.The Bcl-2 expression in every group treated with arsenic trioxide was lower than that of asthmatic group, and the effect was in a dose-dependent manner.CONCLUSION: There are therapeutic effects of arsenic trioxide on asthma.The mechanisms may be ascribed to the effects of arsenic trioxide on apotosis and activation and the Bcl-2 expression of T cells.

Key words: asthma, T cells, Bcl-2 gene, arsenic trioxide, mice