RU486对早孕猕猴腺垂体-肾上腺皮质糖皮质激素受体表达的影响

Effect of RU486 on the expression of glucocorticoid receptors on anterior pituitary-adrenal cortex system in early pregnant rhesus monkeys

目的探讨大剂量的RU486对早孕猕猴腺垂体-肾上腺皮质系统(PAS)的糖皮质激素受体(GR)的表达变化。方法15只早孕猕猴随机分为空白对照组、赋形剂组和RU486组。空白对照组不予任何处理,赋形剂组和RU486组每天分别鼻饲0.5%CMC-Na(1ml/mg)和RU486(15mg/kg),3d后处死动物。应用单克隆抗体链菌素亲生物蛋白过氧化酶(SP)免疫组织化学方法观察腺垂体-肾上腺皮质GR的表达情况,并用电子计算机图像分析技术进行处理。结果RU486组猕猴妊娠终止,该组腺垂体、肾上腺皮质GR的表达减少,积分光密度值分别为32.9±6.6、64.9±4.5,与空白对照组(61.2±3.9、95.9±20.9)的差异有统计学意义(P<0.05)。空白对照组和赋形剂组妊娠没有终止,赋性剂组腺垂体、肾上腺皮质GR积分光密度值分别为63.8±4.8、91.3±14.7。与空白对照组GR表达的差异无统计学意义(P>0.05)。结论RU486可使早孕猕猴腺垂体-肾上腺皮质的GR表达下降,提示RU486的抗糖皮质激素作用可能是其终止妊娠的机制之一。

Objective To obsever the effect of RU486 on the expression of glucocorticoid receptors （GRs） on anterior pituitary and adrenal cortex in early pregnant rhesus monkeys. Methods Fifteen animals with early pregnancy were allocated into tree groups randomly and equally： blank control group, excipient group and RU486 group. The groups were treated with nothing excipient and the antiglucocorticoid RU486 respectively for tree days, in order to observe the change of GRs on anterior pituitary and adrenal cortex by use of immunohistochemistry and computer image analysis technology. Results The pregnancies of rhesus monkeys in RU480 group stopped. Expression of anterior pituitary and adrenal cortex in the RU480 group decreased. The value of integral photodensity of anterior pituitary and adrenal cortex in this group were 32.9 ±6.6 and 64.9 ±4.5 respectively, which were statically different with that of the blank control group： 61.2±3.9 and 95.9±20.9 （P〈0.05）. The pregnancies of rhesus monkeys in blank control group and expedient group continued. The value of integral photodensity of anterior pituitary and adrenal cortex in expedient group were 63.8±4.8 and 91.3±14.7 respectively, which had no statistic difference with that of the blank control group （P〉0.05）. Conclusion The GR concentrations on anterior pituitary and adrenal cortex system in early pregnancy rhesus monkeys decreased by RU486. It suggest that the antiglucocorticoid function of RU486 may take part in the mechanism of RU486 in causing abortion.