LHRH-A对孕中期大鼠抗妊娠作用的研究

本文观察了[D-Ala⁶,Pro⁹-Ethylamide¹⁰]-LHRH(LHRH-A)对孕中期大鼠的抗妊娠作用。结果显示:在孕9～11d sc 200μg/d LHRH-A,血浆孕酮水平自第二次给药后明显下降(P<0.05),给药大鼠均流产终止妊娠;LHRH-A的抗妊娠作用可被醋酸甲地孕酮所拮抗;LHRH-A对体外培养的假孕大鼠和孕d 9大鼠黄体细胞分泌孕酮有明显的直接抑制作用。

STUDIES ON THE ANTIPREGNANCY EFFECT. OF LHRH-A IN MID GESTATIONAL RATS

In the present study, the antipregnancy effect of (D-Ala6, Pro9-Ethylamide10) LHRH (LHRH-A) on midgestation rats was observed. The results indicate that LHRH-A could terminate pregnancy of all experimented rats by abortion after subcutaneous administration of 200 micrograms LHRH-A (dissolved in vegetable oil) once a day at days 9 to 11 of their pregnancy. It was also found that the serum progesterone level was significantly lowered after the administration of LHRH-A (P less than 0.05); the concomitant administration of megestrol acetate with LHRH-A could almost completely block the antipregnancy effect of LHRH-A on the midgestation rats; LHRH-A showed a strong direct inhibitory effect on luteal cell progesterone secretion in pseudopregnant and midgestation rats. Hence, it is considered that the probable mechanisms for the antipregnancy effect of LHRH-A may be mainly due to the decrease of serum progesterone level caused by the direct inhibitory effect of LHRH-A on midgestation corpus luteum progesterone production.