橐吾中倍半萜对二氢吡啶类受体的作用研究

 目的：观察8个倍半萜类化合物对二氢吡啶类受体结合的作用和对离体血管张力的影响。方法：用［3H］尼群地平对猪心室肌微粒体膜受体结合方法和家兔离体血管条实验对化合物的体外作用进行研究。结果：化合物Ⅰ、Ⅱ、Ⅲ对尼群地平与受体结合有明显抑制作用，其IC₅₀分别为2.0×10^-5mol·L^-1，2.7×10^-5mol·L^-1和3.9×10^-5mol·L^-1，其余化合物作用较弱。这些化合物抑制受体结合的作用强度与结构中母核与取代基的改变有关，而取代基的变化对活性的影响更重要。化合物Ⅱ、Ⅲ对高K+引起的兔胸主动脉收缩有剂量依赖性的抑制作用。结论：这类化合物有钙拮抗作用，作用机制可能与影响二氢吡啶类受体有关；它们作用有量效关系和构效关系，提示有以此为先导进行深入结构改造和构效关系研究的价值。

Study of effects on dihydropiridine receptor of furanosequiterpenes from Ligularia virgaurea

To study the effects of eight sesquiterpenes on dihydropiridines receptor binding and isolated vascular tension. METHODS: ［3 H］-Nitrendipine receptor binding assay and rabbit isolated thoracic artery tension experiment. RESULTS: Compound Ⅰ, Ⅱ and Ⅲ significantly inhibited the binding of ［3 H］-nitrendipine to pig heart membranes with IC50 of 2.0×10-5 mol*L-1, 2.7×10-1 mol*L-1 and 3.9×10-1 mol*L-1, respectively. Inhibitory effects of these compounds were related to both substitutes in the central benzofuran and benzofuran itself, but the substitutes affected biological activity in more extensively than central benzofuran. Compound Ⅰ and Ⅱ inhibited the contraction of isolated rabbit arterial strips induced by K+ in a dose-dependent mannel. CONCLUSION: These compounds are possessed of calcium antagonistic properties. The mechanism of the effect may be due to dihydropiridine calcium channel receptor.