Effects of Flavonoid of Cortex mori on Histamine-induced Tracheal Contraction of Guinea-pig in vitro

[Objective] The aim was to investigate the effects of the flavonoid of Cortex mori(FCM) on histamine(His)-induced tracheal contraction of guinea-pig in vitro.[Method] Guinea-pig tracheal smooth muscle was isolated and its contraction was induced by His.The antagonistic effects of FCM were studied in vitro.[Result] FCM relaxed the normal tone of isolated guinea-pig tracheal sheets,the-lgEC50(g/ml) for FCM was 3.96±0.65.FCM inhibited His-induced tracheal contraction of guinea-pig within 60 min.The-lgIC50 of FCM on contraction induced by 10-5mol/L histamine was(3.81±0.23) g/ml.[Conclusion] FCM could inhibit the histamine-induced tracheal contraction of guinea-pig in vitro.