国产米非司酮对早孕家兔子宫收缩和肌电活动的影响

Effects of Mifepristone on Contractile and Electrical Activity of Rabbit Uterus in vivo during Early-pregnancy

为了解国产米非司酮对早孕家兔子富收缩及其肌电活动的影响,以及子宫对前列腺索的敏感性变化,同时观察药物终止早孕效果,于动物交配后第9～10天作无菌手术,在一侧子宫肌壁内埋植铂金丝电极,宫腔内安放一橡皮小水囊,通过多导生理记录仪同时记录宫内压及其肌电活动。术后第2天开始灌胃给药,5mg/(kg·d),连续3d。结果给药组子宫活动增强,出现逐渐增强的官缩波及暴发式排放的丛状肌电波,胚胎死亡吸收;相反对照组子宫处于相对静息状态,胚胎继续发育存活。

The aim of this study was to evaluate the effect of mifepristone of Chinese made on contractile and electrical activities of rabbit uterus and the sensitivity changes of myometrium to prostaglandin derivative l5-methyl-PGF2α in vivo during early pregnancy. In the meantime, the effect of the drug on termination of early pregnancy was also observed. The laparotomy was performed under strictly aseptic conditions on the 9-10 th day after mating. If pregnancy was confirmed, one of its uterine horns was exposed, and platinum electrodes (0.1 mm diameter) and a rubbtr water balloon were inserted respectively according to Csapo (1963) method. The pressure changes and the electrical activities were recorded by a multi-purpose polygraph RM150. Mifepristone 5mg/(kg·d) or 0.5 % CMC 1 ml/ (kg·d) was given orally to the treatment and control group from the second day afttr operation for three days. Our results show that 24 hrs after mifepristone administration spontaneous contractions and electric activities of uterus occurred, which were strengthened on the following days. The response of uterus to 15-me-thyl-PGF2α was much sharper in the treatment group than in the control group. In the treatment group, among all of 18 early-pregnant rabbits only one animal with parial embryo survival was found, but in the control group the development of the embryos generally was normal. From the above it becomes obvious that mifepristone can induce termination of early pregnancy in rabbits and increase the stnsiti-wity of myometrium to PG.