Effect of intrauterine exposure to TCDD on key steroidogenesis genes in placenta of male fetal rat
HAN Wei;MA Jing;CHEN Xi;LIU Ya-nan;ZHANG Ai-lian;CHEN Jing-shan;LENG ling;YAN Huan;Jiefang Road Community Health Center,Tanggu,Binhai New Area of Tianjin City;
Objective To observe the impact of intrauterine exposure to TCDD on development and steroidogenesis genes in placenta of male fetal rats. Methods Pregnant SD rats were randomly divided into three groups: low-dose of TCDD group( 100 ng/kg),high-dose of TCDD group( 500 ng/kg) and control group( corn oil only),all were received intragastric administration during 8—14 day after gestation. Record pregnancy outcomes and measure various growth and developmental indicators, meanwhile,the expression levels of steroidogenesis-related genes( P450scc、P450c17、3β-HSD) in placentas of male fetal rats was also detected with real-time quantitative PCR. Results( 1) There were statistically differences( P 0. 05) among groups in liver weights and coefficients of pregnant rats,the liver weight of 500 ng / kg group was significant lower than that of control group.( 2) Adverse pregnancy rate showed statistically differences between exposed groups and control group( P 0. 05).( 3) Body weights of male fetal rats in TCCD-exposed groups were lower than that of controls,while the placental weights were highter than that of control group.( 4) The general growth and development indicators of male fetal rats in TCDDexposed groups showed a reducing trend compared with the control group,but only the tail length of low-dose group had statistically difference( P 0. 05).( 5) The gene expression levels of P450scc,P450c17,and 3β-HSD in fetal male placentas of TCDD exposed groups were obviously lower than that of the control group,their levels in control group were 1. 63 time,1. 42 time,1. 49 time of the 100 ng / kg group and were 1. 63 time,1. 14 time,and 1. 41 time of the 500 ng / kg group,respectively. Conclusion TCDD exposure during gonadal sex determination period could effect general growth and developmental of male fetal rats,and might impact the expression of steroidogenesis key genes in the placenta of fetal male rats.