RU486是具有抗孕酮作用的合成类固醇,其拮抗孕酮的作用可用于催经止孕与诱发分娩等。关于有效给药方法的详细研究资料尚少。现以家兔为对象,研究RU486阻断妊娠的给药条件以及同一给药途径与药量,在妊娠不同时期给药对妊娠的阻断作用。实验动物选择体重2.8～3.2kg的成熟未产雌性日本白色家兔,分笼饲养一个月后交配使之妊娠。为保证妊娠,在交配后立即耳静脉注射hCG 75IU以诱发排卵。实验与结果:1.不同给药途径与给药量的比较:交配后第11天在全麻下开腹,检查子宫内胎儿与卵巢,在确认已着床的胎儿及妊娠黄体的条件下给予RU486。静脉给药用 RU486 is a synthetic steroid with anti-progesterone action, and its antagonistic effect on progesterone can be used to induce pregnancy arrest and induce childbirth. There is little information on the detailed studies on effective methods of administration. Rabbit is now an object to study RU486 blocking pregnancy administration conditions and the same route of administration and dose in different stages of pregnancy on the administration of pregnancy blocking effect. Experimental animals weighing 2.8 ~ 3.2kg of mature female Japanese white rabbits were not produced, sub-cage feeding one month after mating to make pregnancy. To ensure pregnancy, hCG 75 IU was injected into the ear vein immediately after mating to induce ovulation. Experiments and results: 1. Comparison of different routes of administration and administration: Open the abdomen under general anesthesia on the 11th day after mating, check the intrauterine fetus and ovary, and give the fetus under pregnancy and the corpus luteum RU486. For intravenous use