胎盘四氯二苯二噁英表达在胰岛素样生长因子2诱导胎鼠发育异常中的作用  

Role of IGF2 expression in placenta of TCDD-induced fetal rats with development abnormality

作　　者：王珺[1] 赵彦艳[1] 李光宇[1] 李英慧[1] 刘洪[1] 吕晶玉[1] 

机构地区：[1]中国医科大学基础医学院医学遗传学教研室

出　　处：《中国现代医学杂志》2006年第14期2137-2140,2144,共5页China Journal of Modern Medicine

基　　金：国家科技部973项目(001CB510301)

摘　　要：目的研究四氯二苯二噁英(2,3,7,8-tetrachlorodibenzo-p-dioxin,TCDD)对胎鼠生长发育的影响及与胰岛素样生长因子2(insulin-likegrowthfactor2,IGF2)的关系。方法经灌胃给予孕10d大鼠10μg/kgTCDD,20d剖宫取胎,比较实验组和对照组孕鼠妊娠结果,测量两组活胎的身长、体重及胎盘重;用逆转录-实时定量PCR和免疫组化方法检测两组活胎胎盘组织IGF2mRNA及蛋白的表达水平,用甲基化敏感限制酶HpaⅡ酶切—PCR法检测两组胎盘组织IGF2基因DMR1的甲基化程度。结果实验组死胎及吸收胎发生率为12.2%,致畸率为11.6%,活胎身长、体重及胎盘重明显低于对照组;实验组活胎胎盘组织IGF2mRNA及蛋白的表达明显高于对照组;两组IGF2基因DMR1的甲基化程度无差异。结论孕10d给予大鼠10μg/kgTCDD灌胃可导致死胎、吸收胎、畸形胎和胎儿宫内发育迟缓(intrauterinegrowthretardation,I-UGR),TCDD所致胎鼠发育异常可能与胎盘组织IGF2表达增高有关。[Objective] To study the effects of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin （TCDD） on the development of fetal rats. [Methods] A single dose of 10μg/kg TCDD was given to gestation day （GD）10 pregnant rats （ 10 days of gestation period） by gavage. On GD20, the fetuses were taken out and examined. The fetal heights, body weights and the placenta weights of experiment group were measured. The expression of IGF2 in placentas was detected by both quantitative real-time RT-PCR and immunohistochemistry. The methylation of IGF2 DMR1 was analyzed by a methylation-sensitive restriction enzyme Hpa Ⅱ - PCR assay. [Results] In the experiment group, 12.2% of the fetuses was either dead or absorbed, and 11.6% was malformed. For the live fetuses, height, body weight and placenta weight of experiment group were significantly lower than those of the control group. The expression of IGF2 in placentas was remarkably upregnlated after treatment. The two groups show no difference in the methylation status of IGF2 DMR1. [Conclusion] A single oral dose of 10μg/kg TCDD to gestation pregnant rats 10 days of period can lead fetal rats to dead, absorbed, malformed and intrauterine growth retardation （IUGR）. The TCDD led abnormal development in rats may be associated with the upregulation of 1GF2 in placentas, but may not be related to the methylation of 1GF2 DMR1.

关 键 词：TCDD 胰岛素样生长因子-2 发育异常 

分 类 号：Q343.6[生物学—遗传学]