醋酸烯诺孕酮的大鼠抗早孕活性试验

目的探讨醋酸烯诺孕酮(ST-1435)对妊娠大鼠的抗早孕活性。方法妊娠8d大鼠随机分为6组:阴性对照组给予生理盐水皮下注射,阳性对照组给予米非司酮灌胃,实验组给予不同剂量ST-1435皮下注射。各组于妊娠第14天处死,观察妊娠结局;并测定给药前后血清孕酮(P)与黄体生成素(LH)水平。结果单次注射16.0mg/kg剂量ST-1435的抗早孕率83.6%,与米非司酮12.0mg/kg分3次灌服的抗早孕率84.7%相似,与阴性对照组相比有显著性差异(P<0.05)。8.0和4.0mg/kgST-1435单次给药的抗早孕率分别为24.6%和11.7%。单次注射16.0或8.0mg/kgST-1435对妊娠大鼠血清LH和P有明显的抑制作用。结论单次注射16.0mg/kgST-1435有与米非司酮12.0mg/kg分3次灌服相似的抗早孕效果。但8.0和4.0mg/kg的ST-1435单次给药无明显的抗早孕效果。此外大剂量的ST-1435对妊娠大鼠的血清P和LH有抑制作用。

Effect of ST-1435 on the termination of early pregnancy of rats

Objective: To investigate the effect of ST-1435 on the termination of early pregnancy.Methods: The pregnant rats (day 8 of pregnancy) were randomly divided into 6 groups: the rats in the negative control group were given physiological saline; the rats in positive control group were given mifepristone; and other four groups were given different doses of ST-1435. All rats were killed on day 14 of pregnancy and the results of pregnancy were observed. The levels of serum progesterone and luteinizing hormone (LH) before and after treatment were measured.Results: The single dose of 16 mg/kg ST-1435 had a significant anti-early pregnancy effect. The (termination) rate (83.6%) was very similar to that of 12.0 mg/kg mifepristone group (84.7%), which was significantly higher than that of negative control group (P<0.05). The termination rates in 8 mg/kg and 4 mg/kg ST-1435 were 24.6% and 11.7%, respectively. The serum levels of LH and progesterone were significantly decreased after 16 mg/kg or 8 mg/kg of ST-1435 given.Conclusion: The single dose of 16 mg/kg ST-1435, but not 8 mg/kg or 4 mg/kg ST-1435, had a significant anti-early pregnancy effect. Large dose of ST-1435 can inhibited the serum levels of LH and progesterone in rats.