Effect of bisphenol-A given neonatally on the genesis of rat oviduct

尽管在聚苯乙烯和环氧树脂制造中使用的双酚a （BPA）被认为是啮齿动物体内一种强有力的内分泌干扰物，但其对生殖功能的具体影响尚不清楚。我们已经报道过用BPA处理的雌性大鼠在出生后60天表现出有规律的发情周期，并且有带有卵泡和黄体的卵巢。然而，在怀孕的第10天和第18天，他们有一些胎儿肿胀和子宫异常肿胀。在本报告中，研究了从出生之日起每天7次注射1毫克BPA的T系雌性大鼠的子宫和输卵管。bpa处理的大鼠在第60天左右表现出规律的发情周期。bpa处理大鼠和对照大鼠在成年期用黄体酮和雌二醇治疗7天的第4天子宫损伤后，子宫形成蜕膜瘤，但前者的反应比后者小。经bpa处理的大鼠第60天的发情次数比对照组少。bpa处理的大鼠在第60天出现INF闭塞和消失，上皮和间质组织出现炎症。输卵管畸形大鼠卵巢囊内多有卵，壶腹内无卵。直到第30天才出现异常，并在第40天发生。雌性大鼠同样给予0.01mg雌二醇-17b处理，在第60天左右出现正常的发情周期和类似的输卵管损伤。这些发现表明，在BPA处理的怀孕大鼠中，胎儿的减少可能至少部分是由于输卵管畸形导致的卵子运输失败，而不是子宫反应，引起BPA的雌激素作用。已知输卵管畸形中含有炎症和粘连是人类女性不育的重要因素。本研究可作为评价内分泌干扰物对女性生殖障碍影响的有用模型之一

Although bisphenol-A (BPA) used in the manufacture of polystyrene and epoxy resins is thought to be a potent endocrine disrupter in rodents, the detail effect on the reproductive function is still obscure. We have already reported that female rats treated with BPA neonatally showed regular estrous cycles at 60 days, and contained ovaries with follicles and corpora lutea. However, they had a few fetal swellings and abnormal swellings in the uteri on Days 10 and 18 of pregnancy. In the present report, uteri and oviducts were investigated in female rats of the T strain given 7 daily injections of 1 mg BPA from the day of birth. The BPA-treated rats showing regular estrous cycles around Day 60. In both the BPA-treated and control rats, the uteri formed deciduomata in response to uterine trauma given the 4 th day of a 7-day treatment with progesterone and estradiol in aduthood, but the resposne was smaller in the former than the latter. The number of ova ovulated in the oviduct at the first … More estrus after Day 60 was fewer in the BPA-treated rats than in the controls. The BPA-treated rats showed occlusion and disappearance of the INF, and inflammation in the epithlium and stromal tissue on Day 60. The rats with oviduct malformation often contained ova within the ovarian capsule, but not in the ampulla. The abnormality was not evident until Day 30 and occurred Day 40 onward. Female rats likewise treated with 0.01mg estradiol-17b showed normal estrus cycles and similar damages in the oviduct around Day 60. These findings indicate that the reduction of fetuses in the BPA-treated pregnant rats may be accounted, at least in part, for by the failure in transport of the ovum due to the malformation of oviducts, rather than to uterine response, eliciting estrogenic action of BPA. It is known that the oviduct malformation containing inflammation and adhesion in the INF is an important factor for female infertility in human. The present study may be one of useful models for evaluation of the effect of endocrine disruptors on the female reproductive disorder Less