鱼腥草对家兔小肠平滑肌收缩活动和电活动的影响

Effect of Yuxingcao on Activities of Intestinal Smooth Muscle Contraction and Electricity of Rabbits

目的:探讨鱼腥草对家兔小肠平滑肌收缩活动和电活动的影响,为对抗鱼腥草的不良反应提供理论依据。方法:取健康家兔,雌雄不拘,将小肠离体后恒温灌流,观察鱼腥草对家兔小肠自发收缩活动和电活动的影响,并探讨其作用机制。结果:鱼腥草使家兔小肠平滑肌收缩活动和电活动的幅度和曲线下面积明显减小,并呈剂量依赖关系;而对收缩活动和电活动的频率均无明显降低作用。以收缩幅度为指标,用Logit法计算IC50为70.94 mg/mL。心得安和L-NAME可部分阻断鱼腥草对家兔小肠平滑肌收缩活动的抑制作用。鱼腥草显著抑制氯化钡诱发的依内Ca2+性收缩,而对依外Ca2+性收缩无明显影响。结论:鱼腥草显著抑制家兔小肠平滑肌收缩活动和电活动。其抑制收缩活动机制可能是通过激动β受体实现的,也与使NO浓度增加有关,鱼腥草还能抑制肌浆网释放Ca2+。

Objective:to discuss the effect of Yuxingcao on activities of intestinal smooth muscle contraction and electricity of rabbits to supply theoretical basis for anti-untoward reaction of Yuxingcao.Methods: healthy rabbits,male or female,was given perfusion under constant temperature with small intestine peeled off so to observe the effect of Yuxingcao on activities of smooth muscle and electricity and its functional mechanism.Results: Yuxingcao made less the scope and curve of activities of intestine smooth muscle contraction and electricity and became dosage dependent;but there was no significant decrease on their frequency.With contraction scope as criteria,IC50 was 70.94mg/ml by Logit method.Xinde'an and L-NAME could blockade in part its inhibition to the activities of intestine smooth muscle contraction.Yuxingcao could significantly inhibit the inner Ca2+ contraction induced by barium chloride while had no significant effect on the outer Ca2+ contraction.Conclusion: Yuxingcao can significantly inhibit the activities of smooth muscle contraction and electricity of rabbits,whose mechanism is finished by activatingβreceptor and also related to increasing NO concentration;Yuxingcao can also inhibit sarcoplasm from releasing Ca2+.