黄芪甲甙对大鼠离体肠系膜动脉血管舒缩功能的影响

Effect of astragaloside Ⅳ on contraction and relaxation on isolated rat mesenteric arteries

目的:观察黄芪甲甙对大鼠离体肠系膜动脉舒缩功能的影响,并探讨其可能机制。方法:分离肠系膜动脉1～2级分支制备离体肠系膜血管环固定于微血管张力测定仪,观察黄芪甲甙对血管环舒缩功能的影响。结果:①不同浓度的黄芪甲甙(30mg/L和100mg/L)孵育后,苯肾上腺素引起的血管收缩较对照组明显下降(P<0.05或P<0.01)。②累积浓度的黄芪甲甙对苯肾上腺素(2×10-6mol/L)预收缩的内皮完整或去内皮肠系膜动脉血管环均产生浓度依赖性的舒张作用,中高浓度的黄芪甲甙(10mg/L、30mg/L和100mg/L)对内皮完整组的舒张作用明显强于去内皮组(P<0.05或P<0.01)。③累积浓度的黄芪甲甙对KCl预收缩的肠系膜动脉血管环张力无明显影响(P>0.05)。④L-NAME(10-4mol/L)预处理能显著减弱黄芪甲甙的舒血管作用(P<0.05或P<0.01)。结论:黄芪甲甙具有一定的内皮依赖性舒张血管作用,且主要通过NO途径发挥作用。

Objective： To observe the effect of astragaloside Ⅳ on contraction and relaxation on isolated mesenteric arteries, and to study its underlying mechanisms. Methods： The isolated mesenteric arteries segments were mounted in the Danish Myo Technology Multi Wire Myograph System （DMT）. The effect of astragaloside Ⅳ on contraction and relaxation on the arteries was observed. Results： ①After incubation in the solution of Astragaloside Ⅳ of different concentrations （30 mg/L and 100 mg/L）, vasoconstriction induced by ethyl phenyllphrine obviously declined compared with control group （P〈 0.05 or P〈 0.01）. ②）Astragaloside Ⅳ relaxed mesenteric artery rings （both with and without endothelium） in concentration-ependent manner, which bad been precontracted with ethyl phenyllphrine （2 × 10^-6 mol/L）, while the relaxation of the rings with endothelium was significantly stronger than that of rings without endothelium （P〈 0.05 or P〈 0.01 ）. ③Astragaloside Ⅳ had no significant effect on those which had been precontracted by KCI（P〉0.05）. ④re-treatment with L-NAME （10^-4 mol/L） significantly decreased the effect of vasodilatation of Astragaloside Ⅳ （P〈0.05 or P〈 .01）. Conclusion： Astragaloside Ⅳ can endothelium- dependently dilate vessels to some extent, and it plays this function mainly through the NO pathway.