母鼠微量镉暴露对子代的影响

Effect of maternal exposure to trace cadmium in offspring rats

目的研究妊娠期及哺乳期微量镉暴露对子代的影响。方法将SD孕鼠32只随机分为4组：镉组（A组）、己烯雌酚组（B组）、镉加他莫昔酚组（C组）和正常对照组（D组）,每组8只。A组于孕期第9、11、13天及产后隔日腹腔注射氯化镉1.5mg/（kg·d）;B组于妊娠第9~17天及产后隔日皮下注射己烯雌酚100μg/（kg·d）;C组注射氯化镉的同时给予雌激素受体拮抗剂他莫昔酚50mg/（kg·d）;D组注射与镉等体积生理盐水。妊娠第18天,每个组随机选取4只进行剖宫产取胎鼠,记录胎鼠数量、体长、胎盘重量,计算胎鼠雌雄性别比例;产后30天,记录仔鼠重量及雌雄性别比例。结果与对照组比较,各组胎鼠、仔鼠数量以及雌雄性别比例没有明显差异（P〉0.05）;镉组和己烯雌酚组胎盘重量,胎鼠和仔鼠体重及胎鼠体长均低于对照组（P〈0.05）。结论微量镉对妊娠数量及雌雄性别比没有明显影响;微量镉对胎鼠及仔鼠的生长发育可产生抑制;镉和己烯雌酚对胎鼠和仔鼠的影响作用相似,表明镉具有雌激素样效应。

Objective To investigate the effect of maternal exposure to trace cadmium in off-spring testes.Methods32 pregnant female SD rats were randomly divided into 4groups with 4in each group：CdCl2treated group（group A）was intraperitoneally injected with CdCl2（1.5mg/kg.d）on 9th,11 th,13th day of the gestation period and every other day during lactation respectively.DES group（group B）was subcutaneously injected with DES（100μg/kg.d）from day9 th to 17 th of gestation period and every other day during lactation respectively.CdCl2 ＋TMX group（group C）was treated with CdCl2（same as above）＋TMX（50mg/kg.d）.The control group（group D）was treated with normal saline instead of CdCl2 with same dose.On day 18 of gestation period,4pregnant rats which randomly selected of each group were killed,the rats fetuses were removed.The weight of fetuses and placenta,body length,sex ratio were recorded.On day 30 th after parturition,the weight and sex ratio of off-spring rats were recorded.Results Compare with group D,there were no significant alternation in the number and sex ratio of off-spring rats among each group（P〉0.05）.The placenta weight,body weight and length of fetuses was significantly decreased in group A and group B（P〈0.05）.Conclusion Trace cadmium has no effect on the number and sex ratio of off-spring rats.Trace cadmium has no effect on growth and development of off-spring rats.The cadmium is a definite environmental endocrine disruptor which has the similar effect as estrogen.