RU_（486）对大鼠早、中期妊娠影响的研究

Effcts of RU_(486) on Early and Middle Stage of Pregnant Rats

应用光、电镜方法观察ＲＵ４８６对早期和中期妊娠大鼠脑垂体、卵巢、子宫、胎盘及肝脏的影响。妊娠大鼠分别在受孕第７天（ｄ７）和第１０天（ｄ１０）给药１．２５ｍｇ／只。中期妊娠大鼠给药后２４ｈ全部流产，蜕膜坏死；４８ｈ子宫内膜修复正常。黄体细胞内脂滴增多、退变。血清孕酮水平低于对照组。早期妊娠大鼠给药后４８ｈ，个别胚胎发育与对照组相似，其余胚胎和胎盘均解体，其中２例子宫已修复。黄体和脑垂体促性腺激素细胞的结构及血清孕酮水平与对照组比较无明显差异。提示：ＲＵ４８６对大鼠抗中期妊娠效果比抗早孕好。

The effect of RU486 on early and middle stage of pregnant rats was observed with light and electronic microscopes. Two groups of pregnant rats were administered with the dose of 1. 25mg/ rat in 7th(d7) and 10th (d10) pregnant day respectively. After being administered for 24h 9 the middle stage of pregnant rats all aborted and decidua was necrosed; for 48h, uterus endometrium had been restored to normal. The lipid droplets in luteal cells increased, and the level of serum progesterone was significantly lower than that in the control group. The state of development of some embryos in two cases among the early pregnant rats were similar to that in the control group after being administered for 48h, embryo and placenta of others all disintegrated, but in two rats their uterus had been restored. There were no significant difference in the structure of corpus luteum and gonadotroph in hypophysis as well as in the level of serum progesterone of experimental and control groups, These results indicated that the anti-pregnant effect of RU486 in middle stage pregnancy rats was better than that in the early stage ones.