利洛司酮终止早孕作用的实验药效学研究

The Pharmacodynamic Experiment of Lilopristone in Termination of Early Pregnancy

利洛司酮与米非司酮均为孕酮受体拮抗剂，它们能在受体水平阻断孕酮作用而发挥催经止孕作用。本文将国产利洛司酮与米非司酮的实验药效学进行了比较性研究，结果表明：利洛司酮与米非司酮经口给药终止小鼠早孕的半数有效量即ED_50(95%可信限）分别为0.38mg／kg(0.27～0.55mg／kg）及0.67mg/kg(0.43～1.06mg／kg），两者药效有显著性差异（P＜O.05）；其终止大鼠早孕的ED_50（95％可信限）为1.06mg/kg(0.68～1.64mg／kg），及2.46mg／kg（1.72～3.51mg／kg），两者药效有极显著性差异（P＜0.01）。此外，利洛司酮经口给药与塞普酮肌内注射给药联合应用时，终止小鼠早孕的效果呈明显的协同效应。

Lilopristine and Mifepristone are steroid derivatives with antiprogestrogen property.They block progestrone receptor(PR) and show menses-induction and pregnancytermination effects.In this study,the pharmacodynamic properties of Lilopristone and Mifepristone were compared in experiment.The results are summarized as follows:The oral ED_50 with 95％ limits of confidence for Lilopristone in termination of early pregnancy in mice was 0.38mg／kg(0.27～0.55mg／kg),while ED_50 of Mifepristone was 0.67mg／kg(0.43～l.06mg／kg)、Significant difference has been revealed(P＜0.05).Results of studies in Sprague Dawley rats showed that the ED_50(oral) of Lilopristone was l.06mg／kg)(0.68～l.64mg／kg),while that of Mifepristone was 2.46mg／kg(1.72～3.51mg／kg).Very significant difference was found(P＜0.o1).Interceptive of treatment with Lilopristone (oral) in combination with a PGs-analogue Sulprostone(i.m.) in mice was assessed.The qvalue was l.29(P＞0.05).Lilopristone in combination with Sulprostone showed syneristiceffect.