Testosterone administration to adult rats differentially modulates androgen and oestrogen receptor-α expression in reproductive organs and pituitary.

Regulation of androgen receptor (AR) and oestrogen receptor α (ERα) expression has direct bearing on the physiology of male reproductive organs. With the help of three independent tools of immunohistochemistry, western blotting and RT-PCR, AR and ER α receptor expression was examined in the testis, epididymis, prostate, seminal vesicle and pituitary of adult rats following testosterone enanthate (TE, 3 mg/100 μl of olive oil/rat per week) intervention for 15 and 30 days. TE administration reduced AR immunoexpression which coincided well with the decline in the receptor protein and transcript levels. In contrast, ERα was found overexpressed in all the organs. While weights of testis and epididymis decreased significantly, those of prostate, seminal vesicle and pituitary demonstrated an upward trend. Spermatogenesis was adversely affected with decline in number of germ cells per tubule and increased prevalence of germ cell apoptosis. Increase in serum and decrease in intra-testicular levels of testosterone were found significant (P < 0.001) in both 15 and 30 days treatment groups. Serum follicle stimulating hormone declined significantly (P < 0.001) at the end of 30 days treatment. Taken together, the above findings indicate that the testosterone intervention differentially modulates, AR ERα expression, which is associated with hypospermatogenesis and increased germ cell apoptosis.