米非司酮对子宫内膜异位症大鼠腺垂体促性腺细胞形态结构影响

目的观察米非司酮对子宫内膜异位症大鼠腺垂体卵泡刺激素(FSH)、黄体生成素(LH)细胞形态结构的影响,探讨其可能的作用机理。方法选发情周期规律,80~90日龄Wistar雌性大鼠建立子宫内膜异位症模型,分为实验组:给不同剂量米非司酮灌胃(10、255、0 mg.kg-1.d-1);去势组:切除双侧卵巢;对照组:只给自来水灌胃。分别于4及8周处死动物取垂体进行FSH、LH细胞免疫组织化学观察。结果实验组与对照组比较阳性细胞平均密度(D)随用药时间延长减低(P<0.05),阳性细胞平均直径(Φ)随药物剂量加大、用药时间延长而变小(P<0.05);去势组阳性细胞平均D及平均Φ增加,随时间延长更加明显。结论米非司酮可能通过下调子宫内膜异位症大鼠腺垂体促性腺细胞分泌功能,影响卵巢激素的分泌,导致异位子宫内膜萎缩,可能为该药治疗子宫内膜异位症的机理之一。

Effect of mifepristone on morphology of adenohypophysial gonadotropic cells in rat with endometriosis

Objective: To observe the effect of mifepristone on the appearance and structure of adenohypophysial follicle-stimulating hormone-secreting cells (FSH cell) and luteinizing hormone-secreting cells (LH cell) in rat with endometriosis.Methods: Wistar female rats with regular estrus cycle and 80~90 days of age were used to establish the models of endometriosis. The different dosages of mifepristone (10 mg·kg~(-1)·d~(-1), 25 mg·kg~(-1)·d~(-1), 50 mg. kg~(-1)·d~(-1)) were given by pouring into stomach (ig.) of rats in the experiment group. The tap water was given in control group. The rats in ovariectomized group only had their bilateral ovaries (removed) without administration of mifepristone. The density and morphology of FSH cell and LH cell in (hypophysis) were studied by immunohistochemistry 4 and 8 weeks later.Results: As compared with the control group, the density of positively stained cells in the hypophysis of experiment group was lower with longer administration of mifepristone (P<0.05) and the mean diameter of positive cells reduced with increase in dosage and administration days (P<0.05). The density and mean diameter of positive cells in the hypophysis were significantly increased with extension of the time in ovariectomized group.Conclusion: It is possible that mifepristone influences the secretion of ovarian hormones by down-regulating the secretory function of gonadotrophic cells in adenohypophysis of rats with endometriosis and (results) in atrophy of ectopic endometrium. This finding is probably one of the mechanisms of mifepristone for endometriosis.