Transcription and translation of estrogen receptor-β in the male reproductive tract of estrogen receptor-α knock-out and wild-type mice

Estrogen receptor-alpha (ER alpha) has been identified in the male reproductive tract, but the role of estrogen in the male has not been well characterized. In vivo mutations in ER alpha genes have demonstrated the necessity for ER alpha-mediated action in male fertility. We asked whether both ERP messenger RNA and protein were present in the male reproductive tract of wild-type and ER alpha knock-out (ER alpha KO) mice, and whether ERP could compensate for the lack of ER alpha in infertile male ER alpha KO mice. Immunohistochemical localization with both N- and C-terminal anti-ER beta antibodies demonstrated that ER beta is present in the Leydig cells of the testes and in the epithelium of both the efferent: ductules and the initial segment of the epididymis. RT-PCR amplification was used to confirm ER beta transcription in these tissues. In conclusion? we observed that ER beta messenger RNA and protein continue to be expressed in the Leydig cells, elongated spermatids, efferent ductules, and the initial segment of the epididymides of ER alpha KO mice, but the presence of ER beta is not able to compensate for the absence of ER alpha in male reproductive function.