The concentrations of testosterone and dihydrotestosterone (DHT) were measured in the testis and in different segments of the epididymis and vas deferens of adult mice. There were marked regional variations in the concentrations of testosterone and DHT from the testis to the caudal part of the vas deferens. In the testis, testosterone was the predominant androgen (364 +/- 90 ng/g) while DHT was weakly represented (8 +/- 2 ng/g). Qualitative and quantitative changes occurred in epididymis: DHT was the main steroid in the caput (29.3 +/- 2.7 ng/g) and corpus (33.1 +/- 4.4 ng/g) while testosterone and DHT were in similar quantities in the cauda (18.6 +/- 2.6 and 19.0 +/- 2.7 ng/g, respectively). The proximal region of the vas deferens contained higher amounts (71.4 +/- 8.0 ng/g) of androgens (testosterone + DHT) than did the caput epididymidis (39.1 +/- 3.3 ng/g). Testosterone was the predominant androgen in each part of the vas deferens and its concentrations decreased from the proximal (64.5 +/- 7.5 ng/g) to the caudal (26.9 +/- 4.3 ng/g) region. Castration and section of the efferent ducts of the testis showed that the epididymis received testosterone essentially via the blood supply and that epididymal DHT was produced locally from circulating testosterone.

Kidneys of adult male mice are larger than those of females because of both cellular hyperplasia and hypertrophy. Administration of testosterone to adult female mice induced cellular hypertrophy but not hyperplasia, so that the weight of the kidney remained smaller than in male mice. The sexual dimorphism in kidney size is not congenital but programmed by neonatal endogenous androgens and expressed between 30 and 40 days of age. Treatment of newborn males with cyproterone acetate and of newborn females with testosterone induced female and male patterns of renal growth respectively. It appears that neonatal endogenous androgens are required to induce the characteristic cellular hyperplasia of the kidneys of male mice. Manipulation of androgen levels during neonatal and prepubertal life was found to affect the growth response of the kidney to androgens in adult male and female mice.

This study was conducted to evaluate the growth and biochemical responsiveness of the epididymis, vas deferens and seminal vesicles of adult mice exposed to cyproterone acetate during the first 10 days of life. Results indicate that the weight and protein content of sex accessory organs were significantly depressed, testosterone and dihydrotestosterone concentrations were unaffected or increased, the number of cytosolic androgen-binding sites was slightly or significantly reduced. The efficiency of exogenous testosterone in promoting growth and protein synthesis in target organs of castrated adult males was significantly lowered by neonatal cyproterone acetate treatment. It is concluded that a deficient androgenic stimulation during neonatal life induces a limited response of sex target organs to endogenous or exogenous androgens in adulthood.

No abstract

In this study, changes in the number of androgen binding sites that occur in cytosols of epididymis, vas deferens and seminal vesicle of mice from 10 to 90 days of age are described. Specific saturable binding of [3H]R‐1881 by cytosols of the three organs at all time points studied and age‐related differences in the number of binding sites measured were observed. Cytosolic androgen receptor levels in all three organs studied were found to decrease with increasing age, regardless of whether the binding was expressed relative to weight of tissue, cytosolic protein or cellular DNA. The most pronounced change in androgen receptor levels (from 442 to 50 fmol/mg protein) was observed in the epididymis between 10 and 30 days of age. In these three organs there was no significant correlation between androgen (testosterone + dihydrotestosterone) levels and the concentration of androgen binding sites.