甲氨蝶呤对小鼠抗早孕作用的研究

EFFECTS OF METHOTREXATE ON EARLY PREGNANCY IN MICE

用小鼠抗早孕实验，观察甲氨蝶呤（ＭＴＸ）单用和合并用药的抗早孕作用。小鼠于妊娠ｄ７分别一次ｓｃＭＴＸ８，２４和７２ｍｇ·ｋｇ－１可引起胚胎死亡，妊娠ｄ１３死亡率分别为１８０％，５５５％和６０３％。给药后测定血清孕酮水平，妊娠ｄ９未发现明显改变，妊娠ｄ１３其水平明显降低。小鼠于妊娠ｄ７～９注射ＭＴＸ２４ｍｇ·ｋｇ－１连续３ｄ引起胚胎全部死亡。ｈＣＧ和孕酮可拮抗ＭＴＸ的抗早孕作用。ＲＵ４８６可增强ＭＴＸ的抗早孕作用，提示两药合用抗早孕有协同作用。

Single sc injection of MTX at dosages of 8, 24 and 72 mg·kg-1 on day 7 of gestation was found to have a feticide effect in mice. The mortality of fetuses on day 13 of pregnancy was 180%, 555% and 603%, respectively. Treatment with MTX caused a decrease of serum progesterone level on day 13 of pregnancy. Treatment with MTX at a dosage of 24 mg·kg-1 on day 7～9 of gestation terminated total early pregnancy. MTX combined with hCG 10 U/mouse or pregesterone 02 mg/mouse was shown to have antagonistic effect to terminate early pregnancy. Synergism of RU486 combined with MTX on termination of early pregnancy in mice was observed.