妊娠期和哺乳期双酚A暴露对子代雄性小鼠青春期启动及生精能力的影响

Effects of bisphenol A exposure in gestation and lactation on onset of puberty and spermatogenesis in male offspring of mice

目的研究妊娠期和哺乳期双酚A(bisphenol A,BPA)暴露对子代雄性小鼠青春期启动及生精能力的影响。方法将24只健康清洁级C57BL/6妊娠小鼠按体重随机分为3组,分别为对照(含1%乙醇溶液)组和0.2、2.0μg/ml BPA染毒组,每组8只,单笼饲养。从妊娠第6天至哺乳期(仔鼠出生后21 d)结束,母鼠采用自由饮水方式进行染毒。断乳后,每组随机选取8只雄性仔鼠,断乳后正常喂养1个月。记录子代雄性小鼠青春期启动时间;统计小鼠的精子数和畸形精子数,并计算精子畸形率。结果与对照组比较,各剂量BPA染毒组子代雄性小鼠的青春期启动时间提前,精子计数减少,精子畸形率升高,除0.2μg/ml组精子计数外,差异均有统计学意义(P<0.05)。且随着BPA染毒剂量的升高,子代雄性小鼠精子计数呈下降趋势,而精子畸形率呈上升趋势。结论妊娠期和哺乳期BPA暴露对子代雄性小鼠生殖功能具有明显不良影响,使其提前进入青春期并降低生精能力。

Objective To study the effects of bisphenol A（BPA）exposure in gestation and lactation on the puberty initiation and spermatogenesis in offspring male mice. Methods A total of 24 pregnant C57 BL/6 mice were randomly divided into three groups,eight in each,the control group（1% ethyl alcohol）,low dose（0.2 μg/ml BPA） and high dose（2.0 μg/ml BPA）,treated through drinking water,from gestation day 6 to the end of lactation respectively. The time of puberty initiation, the number of sperm and the rate of sperm malformation were determined in male offspring（eight males were selected for each group） fed by normal feed for one month after wean. Results Compared with the control group,the time of puberty initiation and the rates of sperm malformation significantly increased in offspring of lower and higher BPA-exposed groups（P〈0.05）. The sperm counts were decreased in offspring of lower and higher BPA exposure groups,but only the higher BPA exposure groups was significantly lower than the control（P〈0.05）. The sperm number presented decreasing trend,and the rate of sperm malformation presented increasing trend as the BPA dose increased. Conclusion BPA exposure in gestation and lactation has adverse effect on reproductive function in male offspring and may cause early puberty and decrease in spermatogenesis.