皱皮木瓜总黄酮松弛胃肠平滑肌的效应机制分析

Analysis of Pharmacodynamical Mechanisms of Total Flavone from Chaenomels Lagenaria Koidz on Relaxant Gastrointestinal Smooth Muscles

目的：探讨皱皮木瓜总黄酮（FLC）松弛胃肠平滑肌的机制及其与Ca^2＋的关系。方法1采用家兔离体胃底、回肠和结肠带生物测定法，观察FLC对不同激动剂（Aeh和CaCl2）的反应；用原子吸收分光光度仪测定FLC对游离Ca^2＋的影响。结果：FLC产生剂量依赖性抑制Aeh和CaCl2所致家兔胃底、回肠肌条的收缩，非竞争性拮抗Ach和CaCl2累积量效曲线，最大反应压低，FLC和Ver能抑制Ach诱导结肠带依内钙性收缩，对依外Ca^2＋收缩，仅高浓度（0．4％）FLC亦有抑制作用（P〈0．05）。Vcr则无影响．此外，FLC具有一定的Ca^2＋络合作用。结论：FLC松弛胃肠平滑肌与阻断VDC和ROC，减少外Ca^2＋内流和内Ca^2＋释放有关。

Objective： To elucidate the mechanisms of Total Flavone from Chaenomeles Lagenaria Koidz （FLC） on relaxant gastrointestinal smooth muscles and its relationship with Ca^2＋ . Methods： The effects of FLC were studied on the contraction of isolated rabbit gastric fundus,ileum and taenia coli agonized by Ach and Cacl2 ; The effect of FLC were studied on the complex action with Ca^2＋ . Resuits ： In the isolated rabbit gastric fundus or ileum, FLC and Ver were both found to inhibit the contraction induced by Ach and CaC12 in dose - dependent manner,and non - competitively antagonize the Ach or CaCl2 cumulative dose - response curves with a lower maximal response. FLC and Ver inhibited the contraction induced by Ach in Ca^2＋ -free medium, while FLC（0.4% ） but not Ver inhibited the extracellar Ca^2＋ - dependent contraction induced by Ach. In addition, FLC had lightly complexed action with Ca^2＋. Conclusions： The mechanisms of relaxant gastrointestinal smooth muscle of FLC is related to its bloking effect on the voltage dependent Ca^2＋ channel （VDC） and receptor operated Ca^2＋ channel （ROC） and complex action with Ca^2＋.