Cicletanine与Bepridil对大鼠离体胸主动脉环收缩的抑制效应

Inhibitory Effects of Cicletanine and Bepridil on the Contractions of Isolated Rat Thoracic Aorta Rings

采用雄性SD大鼠胸主动脉环标本,用累积给药法制备去甲肾上腺素(NE)与氯化钾(KCl)收缩主动脉环的量效曲线,观察Cicletanine(Cic)与Bepridil(Bep)的抑制效应,比较两者对NE或KCl最大收缩反应(E_(max))的抑制百分率(％)与ED_(50)。结果显示Cic主要抑制NE激动的主动脉环收缩;Bep主要抑制KCl激动的主动脉环收缩。Cic与Bep联孵时,Cic可增加Bep抑制NE激动主动脉环收缩的效应;Bep可增加Cic抑制KCl激动主动脉环收缩的效应。上述作用无内皮依赖性。

The inhibitory effects of cicletanine (Cic) and bepridil (Bep) on norepinephrine (NE)-and KCl-induced contractions were studied in isolated thoracic aorta rings of male Sprague-Dowley rats. It was found that Cic had a more potent effect on NE-induced contraction than on KCHnduced contraction. In. contrast, Bep had a more potent action on KCHnduced contraction. When the aorta rings were incubated with Cic and Bep, a potentialized inhibitory effect was observed on KCh but not NE-induced contractions. These effects were independent of the presence of endothelium. The results suggest that Cic and Bep have different action sites and properties on vascular smooth muscles.