双酚A对大鼠卵泡体外生长和卵母细胞成熟的影响

目的观察双酚A(BPA)对大鼠卵泡体外生长发育及卵母细胞成熟的影响。方法采用大鼠卵泡体外长期培养方法,从12～14d龄的雌性大鼠卵巢中机械性分离腔前卵泡(140～170μm),隔天分别换一半含BPA 0,50,100和150μmol·L-1的培养液,连续培养10d。倒置相差显微镜下观察卵泡发育的形态,计算卵泡存活率、有腔卵泡形成率和卵丘-卵母细胞复合体(COC)排出率,测定卵泡直径,显微镜下观察卵泡的排卵情况以及卵母细胞成熟情况,计算生发泡(GV)、生发泡破裂(GVBD)和第一极体(PB)的形成率;分别于培养2,6和10d时采用磁性酶联免疫法测定培养基中雌二醇和孕酮的分泌量。结果正常对照组卵泡在10d培养过程中,大多数正常对照组卵泡都经历了腔前卵泡、有腔卵泡以及成熟卵泡阶段。与正常对照组相比,BPA 100和150μmol·L-1组的卵泡存活率、有腔卵泡形成率、COC排出率、GVBD率以及PB率均明显降低(P<0.05)。BPA 50μmol·L-1组培养10d时的卵泡直径以及培养6和10d时BPA100和150μmol·L-1组卵泡和卵母细胞的直径均明显降低(P<0.05);与正常对照组相比,BPA 100和150μmol·L-1组卵泡膜细胞和颗粒细胞的增殖受到明显抑制(P<0.05)。与正常对照组相比,BPA 100和150μmol·L-1组在培养6和10d时雌二醇和孕酮含量均显著减少(P<0.01)。结论 BPA 100和150μmol·L-1可抑制大鼠卵泡的生长和卵母细胞的成熟。

Effect of bisphenol A on rat follicle growth and oocyte maturation in vitro

OBJECTIVE To observe the effect of bisphenol A (BPA) on rat follicle in vitro growth and oocyte maturation. METHODS Using in vitro long-term culture method rat follicles, preantral follicles (140-170 μm) were mechanically isolated from 12-14-day-old female rats and randomly divided into BPA 50, 100, 150 μmol·L^-1 groups and normal control group, and then cultured for 10 d. Then the morphology of follicle development was observed under a microscope and follicle survive antrum cumulus-oocyte cell complexes (COC), germinal vesicle breakdown (GVBD) and first polar body (PB) rates were calculated, steroid hormone production, ovulation rate and oocyte maturation rate to evaluate the effect. RESULTS During 10 d of culture, follicles in normal control group the preantral follicles, antral follicles and mature follicle stage. Compared with normal control group, follicle diameter at 10 d in BPA 50 μmol·L^-1 group decreased (P<0.05), follicle diameter and docyte diameter in BPA 100 and 150 μmol·L^-1 groups at 6 and 10 d were reduced(P<0.05). Compared with normal control group, the rates of follicle survival, cavity formation, the release of COC and PB in BPA 100 and 150 μmol·L^-1 groups statistically decreased (P<0.05). In BPA 100 and 150 μmol·L^-1 groups, the proliferation of theca cells and granulosa cell were suffered a different degree of inhibition(P<0.05). Compared with normal control group, the secretion of estradiol and progesterone in BPA 100 and 150 μmol·L^-1 groups were statistically reduced (P<0.01). CONCLUSION BPA≥100 μmol·L^-1 can inhibit follicle development and oocytes mature.