Localization of estrogen receptor α in adult male albino ratreproductive tract: an immunohistochemical study

IntroductionThere is a considerable variation within and between species in reports of estrogenreceptors’ localization in the male reproductive tract.Aim of the workThe aim of this work is to detect sites of estrogen receptor α (ERα) in different partsof the male rat genital system.Materials and methodsEight adult rats were anesthetized and scarified. Testis, efferent ductules, epididymis,vas deferens, and prostate specimens were taken; paraffin sections were preparedand stained with H E and immunohistochemical stains for the detection of ERα.ResultsERα was detected only in Leydig cells of testis. In efferent ductules, ERα wasstrongly expressed in epithelial cells whereas stromal cells were moderately positive.In epididymis, a few narrow cells of the head, some principal cells in the bodyshowed a moderate positive reaction, and very few apical and basal cells in the tailshowed a weak reaction. Stromal cells of the epididymis showed a strong positiveimmunoreaction in the head and body, whereas in the tail they were weakly positive.In the vas deferens, ERα immunopositivity was absent in epithelial cells but wasdetected in the stromal cells. Similarly, prostatic epithelium was ERα immunonegative,whereas stromal cells were immunopositive. The area% of ERα immunoexpression,the mean epithelial number, and the mean stromal number of immunopositive ERαcells showed a significant difference among different parts of the male genital tract.The highest area% of immunoexpression and the number of ERα-immunopositivecells in the epithelium were detected in efferent ductules.ConclusionERα was selectively expressed along the reproductive tract only by Leydig cells oftestis, with the highest expression in the efferent ductules. Therefore, the presentwork reports the effects of exposure to environmental endocrine disruptors, andalso provides potential targets for development of nonandrogen male contraceptivemethods.