中文摘要：

目的通过检测邻苯二甲酸二丁酯（DBP）孕期染毒所致尿道下裂雄性大鼠仔鼠睾酮（T）、雄激素受体（AR）及成纤维细胞生长因子8（FGF8）的表达，研究DBP干预雄激素依赖性FGF8通路致尿道下裂发生的相关机制。方法20只孕鼠随机分为两组，孕14～18d，分别予大豆油及DBP750mg·kg-1·d-1灌胃。仔鼠出生第一天，统计仔鼠出生数、尿道下裂发生率。第七天时，称量雄性仔鼠体重，拍摄尿道下裂图片，分别取两组中尿道下裂仔鼠及正常仔鼠血清和生殖结节（GT），用放射免疫法检测仔鼠血清睾酮含量；用定量逆转录聚合酶链式反应（Real—timequantitativePCR）及WesternBlot检测AR与FGF8表达水平。结果染毒组及对照组产仔数分别为9．10±0．99和12．60±1．26，仔鼠体重（g）分别为9．53±0．12和11．93±0．15，DBP的生殖毒性作用导致染毒组孕鼠产仔数及仔鼠体重明显减少（P〈O．05），雄性仔鼠尿道下裂发生率为37．2Z。染毒组仔鼠血清睾酮浓度（41．85±8．38）ng／L、生殖结节中AR0．404±0．040及FGF80．036±0．004的表达均明显低于对照组睾酮浓度（107．40±24．28）ng／L、AR表达1．669±0．124及FGF8表达0．168±0．004（P〈0．05）。结论DBP对孕鼠有明显的生殖毒性，DBP通过干预雄激素依赖性FGF8信号通路，导致尿道下裂的发生。

英文摘要：

Objective To evaluate the expression of Testosterone, Androgen Receptor and FGF8 in genital tubercle （GT） of hypospadiac male rats following in utero exposure to DBP, to inves- tigate molecular mechanism of DBP on androgen related FGF8 pathway. Methods Twenty pregnant rats were randomly divided into 2 groups and given DBP by gastric intubation at a dose of 0, 750 mg/ kg from gestation day（GD） 14 to GD18. On postnatal day （PND） 1, male pups were examined for hy- pospadias. On PND7, the body weight of male pups were measured and the gross image of hypospadiac genitalia were checked. Real-time quantitative PCR and WesternBlot were used to evaluate expression of AR and FGF8 in the GT. Radio-immunoassay was used to evaluate testosterone concentration in the serum of hypopadiac rats. Results The number and body weight of live pups in the DBP group （9. 10 ± 0. 99 ;9. 53 ± 0. 12 g） was significantly lower when compared with the control group（12. 60 ± 1.26;11.93 ± 0. 15 g） （P〈0. 05）, and the incidence of hypospadias was 37. 2%. Significantly decreased expression of AR and FGF8 were also found in both mRNA and protein levels in the DBP group（AR：0. 404 ± 0. 040;FGF8：0. 036 ± 0. 004）, when compared with the control group（AR： 1. 669 ± 0. 124; FGF8 ： 0. 168 ± 0. 004） （P〈 0. 05 ）. The testosterone concentration of DBP treating group （41.85 ± 8. 38 ng/L） was also lower than control group（107. 40 ± 24. 28 ng/L） （P〈0. 05）. Conclusions Toxic effects of DBP to pregnant rats were seen. The occurrence of hypospadias may be related to the interference on androgen related FGF8 pathway by DBP.