Immunolocalization of Epidermal Growth Factor in Human Fetal, Adult and Cryptorchid Testes and Seminoma

EGF was localized in human fetal, adult and cryptorchid testis and seminoma using an immunohistochemical method. Leydig cells of adult testes stained intensely for EGF while those of fetal testes showed weak staining reaction. In addition, some spermatogonia and occasional peritubular myoid cells of adult testis stained positively. In cryptorchid testis, there were clusters of Leydig cells interspersed between seminiferous tubules with varying staining intensities. The number of positively stained cells in the cryptorchid testis were fewer than that in adult testes. The decrease in the number of Leydig cells producing EGF may account for the spermatogenesis arrest and infertility associated with this disorder.Intense staining of the cytoplasm of seminoma cells was observed, suggesting that the high production of EGF may be related to their invasive property. In conclusion, EGF is produced by human testis and Leydig cells are the principal source of this cytokine.

DEHP诱导的隐睾鼠胰岛素样因子3基因CpG岛甲基化状态研究

目的研究胰岛素样因子3（insulin-like factor3，INSL3）基因在邻苯二甲酸二已酯（DEHP）致小鼠隐睾中DNA甲基化的状态。方法运用“MethPrimer”软件对INSL3基因进行分析，预测CpG岛，通过甲基化特异性PCR（methylation-specific PCR，MS-PCR）检测INSL3基因CpG岛的甲基化状况，并应用RT—PCR检测INSL3基因在正常组与实验组睾丸组织中的表达情况。结果实验组INSL3基因第一外显子区存在CpG岛甲基化；实验组INSL3基因mRNA表达显著下降。结论INSL3基因第一外显子区CpG岛的异常甲基化导致INSIB在隐睾鼠睾丸中表达降低，可能与隐睾的发生密切相关。