Neonatal estrogen treatment with ß-estradiol 17-cypionate induces in post-pubertal mice inflammation in the ductuli efferentes, epididymis, and vas deferens, but not in the testis, provoking obstructive azoospermia.

Neonatal estrogen treatment (NET) induces morphological changes in male reproductive organs. NET with ß-estradiol 17-cypionate is reported to induce inflammation with stromal-epithelial abnormalities in the prostate and seminal vesicles in post-pubertal mice. The aim of this study was to investigate the histopathology of the testis, ductuli efferentes, epididymis, and vas deferens in mice after NET with ß-estradiol 17-cypionate. No morphological changes in these organs were observed until 4 weeks after NET. However, some inflammatory cells were found in epididymis and vas deferens 6 weeks after NET. Eight weeks after NET, inflammatory cells spread to the ductuli efferentes and inflammation was severe from 6 to 12 weeks after NET. Inflammatory cells were never seen in the whole testis, but cystic dilatation of the rete testes with spermatogenic disturbance was found around the mediastinum testis. Many inflammatory cells emigrated into the lumen of the epididymis, resulting in complete absence of spermatozoa in the vas deferens. Most of the inflammatory cells penetrating into the epithelial layers of epididymal ducts were neutrophils. These results indicate that in post-pubertal mice, NET with ß-estradiol 17-cypionate induces inflammation in the ductuli efferentes, epididymis, and vas deferens, but not in the testis, provoking obstructive azoospermia.

Morphology of accessory sex organs from neonatally DES- and DES-dp-injected mouse.

The neonatal estrogen induces morphological changes in accessory sex organs. We have reported that papillary proliferation in prostates and squamous metaplasia of the epithelium in seminal vesicle occurred and inflammatory cells have emigrated to the lumen through the stroma and the epithelium of organs from neonatal mice treated with beta-estradiol 17-cypionate. In this study, we observed the different effect between neonatal DES and DES-dp on morphological changes in accessory sex organs of mice. After 25 weeks, neonatal estrogen injections induced the infiltration of inflammatory cells in the ventral prostate and squamous metaplasia in the epithelium of seminal vesicles. It was observed that the inflammatory cells have already infiltrated into prostates from DES-dp injected mice after 5 weeks. But DES did not cause the changes in prostates. DES induced organs from a half of mice to involute and inflammatory cell to infiltrate into the epithelium. But these were not seen in organs from another half of mice. DES-dp occurred similar effect of beta-estradiol 17-cypionate on the male accessory sex organs. It remained to be seen whether DES could have estrogen action on accessory sex organ.