【摘要】 目的探讨黄酮类化合物WX-02对兔离体血管环的舒张作用及其作用机制。方法采用兔离体血管环灌流方法,记录WX-02对去甲肾上腺素(norepinephrine,NE)、氯化钾(KCl)收缩的血管环的舒张作用;观察WX-02的舒张作用与内皮的关系;比较WX-02(0.1、0.3mmol·L-1)孵育后CaCl2累积收缩量效曲线的变化及由NE引起的依赖于细胞内钙和外钙收缩反应的变化。结果浓度为0.03~1.0mmol·L-1 WX-02能舒张由致痉剂高钾、去甲肾上腺素引起的收缩;内皮不影响WX-02的舒张作用;浓度为0.1、0.3mmol·L-1 WX-02均能使CaCl2累积收缩量效曲线右移,低浓度的WX-02可能抑制细胞内钙外流,而高浓度的WX-02抑制细胞内钙外流和外钙内流。结论WX-02能够浓度依赖性的舒张血管平滑肌,其作用机制与内皮无关,与阻断不同的钙通道有关。更多还原

【Abstract】 Objective To study the relaxing effect and its mechanism of an flavonoid WX-02 on isolated vascular rings of rabbits.Methods The isolated rings were perfused and the effect of WX-02 on the preparations pre-contracted with NE or KCl was recorded.The effects of WX-02 on endothelium-intact(+EC)and endothelium-denuded(-EC)thoracic aortic rings were observed and the influence on vasoconstrictor effect of CaCl2 and NE after incubation with WX-02(0.1,0.3 mmol·L-1)was compared.Results WX-02(0.03-1.0 mmol·L-1)had a relaxing effect on isolated aorta rings of rabbits precontracted with NE or KCl;the relaxing effect of WX-02 was not affected by endothelial;incubation of WX-02(0.1 mmol·L-1,0.3 mmol·L-1)shifted the concentration-response curves of CaCl2to the right.The outflow of intracellular calcium might be inhibited by low concentration of WX-02(0.1 mmol·L-1),while outflow of intracellular calcium and influx of extracellular calcium might be inhibited by high concentration of WX-02(0.3 mmol·L-1).Conclusions WX-02 has a concentration-dependent relaxing effect on the vascular smooth muscle;the mechanism is not relevant to endothelial,but associated with the inhibition of different Ca2+channels.更多还原