Objective:To explore the effect of Xiaochuanning granules on bronchial asthma. Medicated serum of Xiaochuanning granules was prepared in rat

the anti-degranulation effect on rat basophilc leukemia cell line (RBL-2H3) was observed in vitro. Method: Twenty-five adult Sprague-Dawley rats weighing between 180-200 g were randomly divided into 5 groups (n=5 each). Animals in control group were received normal saline orally while hexadecadrol treated rats received dose of 8.33 mg·L-1 as positive control by gavage. Xiaochuanning granules treated rats were orally received different doses of 40

20

10 g·L-1 respectively for 5 continuous days. Abdominal aorta blood was collected after last administration and medicated serum was separated; anti-degranulation effect was observed with 5% and 10% medicated serum respectively. The real time change of intracellular calcium was recorded by calcium imaging method and the release of β-hexosaminidase was detected by colorimetric method. Result: The medicated serum of Xiaochuanning granules could inhibit both the early and late phase of degranulation after sensitized by Compound 48/80 by the reduction intracellular calcium and β-hexosaminidase release. Conclusion: Medicated serum containing Xiaochuanning granules can inhibit sensitized degranulation in mast cells. This might be one of the mechanisms related to the curative effect of Xiaochuanning granules for treating type I allergic asthma and bronchial asthma in clinic.