Localization of oestrogen receptors alpha and beta in human testis

Cellular localization of oestrogen receptor alpha (ER alpha) and beta (ER b eta) proteins were studied in human testis samples using immunohistochemist ry, and the expression of the corresponding mRNA was examined with reverse transcription-polymerase chain reaction (RT-PCR), Seven men, aged 28-48 yea rs, who underwent diagnostic testicular biopsy because of azoospermia or to give spermatozoa for intracytoplasmic injection for infertility treatment, donated tissue for the study. One of them had anejaculation but normally f unctioning testes, and one was diagnosed as having Sertoli cell-only syndro me (SCOS), In addition, expression of ER beta protein was examined in one t estis sample obtained from a man undergoing a sex change operation. Strong ER beta immunoreactivity was detected in the nuclei of spermatogonia, sperm atocytes and early developing spermatids, Elongating spermatids, mature spe rmatozoa, Sertoli and Leydig cells were all negative for ER beta. The prese nce of ER beta protein was confirmed in Western analysis. With RT-PCR, both wild-type ER beta and ER beta cx, the isoform which represses wild-type ER function, were easily detected. In most cases, ER beta cx mRNA was more ab undantly expressed than wild-type ER beta. The patient with SCOS expressed neither ER beta isoform, Neither ER alpha protein nor ER alpha mRNA was det ected in any of the samples. We conclude that in the human testis, ER beta is likely to be the ER that mediates the effects of oestrogen.