Testosterone and dihydrotestosterone levels in the epididymis, vas deferens and preputial gland of mice during sexual maturation

Abstract

The levels of testosterone (T) and dihydrotestosterone (DHT) in the epididymis, vas deferens and preputial gland were assessed in mice from 1 to 90 days. The weight increase of these 3 organs was proportionately greater than that of the whole body until 50 or 60 days, and they attained their adult histological appearance approximately 20 days prior to puberty. Expressed in ng/g, the concentration of androgens (T+DHT) in the epididymis (14.3 to 36.5), vas deferens (6.6 to 24.0) and preputial gland (1.5 to 4.7) were higher than in plasma (0.2 to 3.6 ng/ml). The concentration of either androgen varied little during sexual maturation and was not correlated with circulating levels. The highest concentration of androgen (T+DHT) was observed at birth suggesting that the neonatal period is crucial for development of the accessory sexual organs. In the epididymis and preputial gland T was the predominant androgen during the infantile phase of development, whilst DHT predominated thereafter. In the vas deferens concentrations of T were always equal to or higher than those of DHT. These results suggest that the ability of the accessory sexual organs to accumulate androgens appears to be more important than the circulating concentration of androgens in determining their growth and differentiation.

A 5-Kilobase Pair Promoter Fragment of the Murine Epididymal Retinoic Acid-binding Protein Gene Drives the Tissue-specific, Cell-specific, and Androgen-regulated Expression of a Foreign Gene in the Epididymis of Transgenic Mice

“…The m5Kb-CAT gene expression was well correlated with the increase of DHT and androgen receptor content that occurs in the mouse epididymis during development (41,42). Castration, efferent duct ligation, and hormonal replacement studies confirmed that androgens, but not other testicular factors, were required to maintain m5Kb-CAT transgene expression in adult animals.…”

Morphometric studies of neonatal estrogen imprinting in the mature mouse prostate

“…However, the significant reduction in epididymal weight with GnRH-A treatment indicates its development as being androgen-dependent. This decline in epididymal weights may be due to elimination of transport of androgen binding protein (ABP) from testis to epididymis as a result of androgen withdrawal ( Jean-Faucher et al 1985, Danzo 1995. While estrogens increased SV size and fluid, they did not appear to antagonize epididymal developmental signal suggesting tissues with common embryologic origin may not share a common critical development period or development signal (Higgins et al 1981).…”

Pem Homeobox Gene Regulatory Sequences That Direct Androgen-dependent Developmentally Regulated Gene Expression in Different Subregions of the Epididymis

“…The principal cells become much more columnar, exhibit extensions of the Golgi apparatus, and have increased numbers of vesicles (51,52). The time frame between days 20 and 30 postpartum is also when there are increases in the levels of AR (53,54), testosterone, dihydrotestosterone (47,55), and the enzyme responsible for dihydrotestosterone production, 5-␣-reductase (56). Thus, the induction of Pem Pp transcription after day 20 could be the result of increased androgen and/or androgen responsiveness, which would also be consistent with our finding that region I is necessary for androgen-dependent transcription.…”