Localization of estrogen receptor alpha in adult male albino rat reproductive tract: an immunohistochemical study

ABSTRACT

There is a considerable variation within and between species in reports of estrogen receptors' localization in the male reproductive tract. The aim of this work is to detect sites of estrogen receptor alpha [ERalpha] in different parts of the male rat genital system. Eight adult rats were anesthetized and scarified. Testis, efferent ductules, epididymis, vas deferens, and prostate specimens were taken; paraffin sections were prepared and stained with H and E and immunohistochemical stains for the detection of ERalpha. ERalpha was detected only in Leydig cells of testis. In efferent ductules, ERalpha was strongly expressed in epithelial cells whereas stromal cells were moderately positive. In epididymis, a few narrow cells of the head, some principal cells in the body showed a moderate positive reaction, and very few apical and basal cells in the tail showed a weak reaction. Stromal cells of the epididymis showed a strong positive immunoreaction in the head and body, whereas in the tail they were weakly positive. In the vas deferens, ERalpha immunopositivity was absent in epithelial cells but was detected in the stromal cells. Similarly, prostatic epithelium was ERalpha immunonegative, whereas stromal cells were immunopositive. The area% of ERalpha immunoexpression, the mean epithelial number, and the mean stromal number of immunopositive ERalpha cells showed a significant difference among different parts of the male genital tract. The highest area% of immunoexpression and the number of ERalpha-immunopositive cells in the epithelium were detected in efferent ductules. ERalpha was selectively expressed along the reproductive tract only by Leydig cells of testis, with the highest expression in the efferent ductules. Therefore, the present work reports the effects of exposure to environmental endocrine disruptors, and also provides potential targets for development of nonandrogen male contraceptive methods: