Abstract: Objective: To study the anti-asthmatic effects of butylphthalide in guinea pig. Methods: This research included isolated tra-cheal smooth muscle and in vivo animal experiments. Antispasmodic effects of butylphthalide at the concentrations of 1, 10, 100 mg/L were observed through spasmodical tracheal smooth muscle of guinea pig induced by acetylcholine or histamine (n=10). After screened, the guinea pigs were divided into control group, model group, dexamethasone(DXM) group, high and low dose butylphthalide groups. The effects of butylphthalide on nitric oxide (NO), endothelin-1 (ET-1) and asthmatic behaviors were observed on the asthmatic guinea pigs that were stimu-lated six times by the excitation fluid (1% ACh:0.05% Hist=1:1). Results: Butylphthalide at the concentrations of 1、10、100 mg/L had an-ti-spasmodic effects on spasmodical tracheal smooth muscle of guinea pig (15.08 ±7.68、42.41 ±13.54、77.56 ±24.82 to acetylcholine, 19.40 ±7.60、56.84 ±11.72、76.35 ±19.40 to histamine), which showed a certain dose-effect relationship. Butylphthalide could prolong asth-matic incubation period (53.3 ±13.2、33.1 ±13.0), improve asthmatic behaviors, reduce NO in serum (78.71 ±19.40、84.75 ±20.97) and ET-1 in bronchoalveolar lavage fluid (24.30 ±5.80、28.50 ±6.31) (P < 0.05, 0.01). Conclusion: Butylphthalide has some effects of anti-asthma and one of the mechanisms is to relieve abnormal increase of NO and ET-1.

Key words: butylphthalide (BPL), antiasthma, guinea pig, nitric oxide (NO), endothelin-1(ET-1)