未性成熟雌性小鼠孕前砷暴露导致植入前胚胎体外发育阻滞

目前研究发现妊娠期环境砷暴露可以导致其后代发育异常如不孕不育、流产、早产、胎儿生长受限、子代先天畸形及性别比例失调等生殖健康问题，而对孕前砷暴露对植入前胚胎发育的影响的研究还不充分.我们选用3-5周龄雌性未性成熟小鼠，按8mg/Kg亚砷酸钠（NaAsO2）剂量隔日腹腔注射一次，共注射8次.结果显示：孕前砷暴露导致小鼠排卵能力明显下降，植入前胚胎大部分阻滞在1-2细胞期.同时发现这些阻滞的胚胎活性氧（ROS）水平明显升高，细胞色素C明显释放，细胞凋亡率明显升高.这些结果说明孕前砷暴露十分危害随后植入前胚胎的发育，这也预示着孕前砷暴露将有可能导致育龄妇女受孕困难.

In Vitro Developmental Retardation of Preimplantation Embryos from Sexually Immature Female Mice by Pregestational Arsenic Administration

Present researches show that environmental arsenic exposure of pregnant woman induces development abnormality of offspring, such as infertility, miscarriage, premature delivery, fetal growth restriction, congenital malformation offspring, gender imbalance, etc. However, the researches of preimplantation embryo from pregestational arsenic exposed immature females are not fully studied. In this study, 3-5 weeks old sex immature female mice were injected intraperitoneally with 8 mg/kg sodium arsenite (NaAsO2) once every other day for 8 times. Our data show that pregestational arsenic exposure results in decreased ovulability and most preimplantation embryonic retardation at 1-2 cell stage. Our results also show that the reactive oxygen species (ROS) level, cytochrome c releasing and apoptosis of blocked embryos were significantly increased. All these results indicate that pregestational arsenic exposure affects the development of preimplantation embryo, which also predicts that pregestational arsenic exposure maybe results in pregnancy problems of women of childbearing age.