The influence of androgens on protein synthesis by cultured rat epididymal tubules.

Rat epididymal tubules maintained in organ culture for 3 days respond to the addition of androgens to the culture media (testosterone and dihydrotestosterone 1 x 10-minus 5 m and 1 x 10-minus 7 m) with an increased incorporation of amino acids into acid-insoluble material. Significant androgenic stimulation is observed only 24 h after addition of hormone, while an inhibitory effect is found at earlier periods. The stimulation seems to be specifically produced by androgens; it is blocked by cyproterone acetate and is not elicited by oestradiol-17beta or corticosterone. The process appears to involve RNA synthesis since actinomycin D suppresses the stimulatory effect of androgen. Evidence suggests that cAMP production is not a primordial step in the response to androgen since dibutyryl cAMP did not mimick the androgenic effect, theophylline did not potentiate the response and alpha,beta-methylene ATP, which competitively inhibits adenyl cyclase, failed to alter the androgenic effect. Radioactive testosterone and dihydrotestosterone added to the culture media showed a preferential intranuclear localization as well as extensive metabolism. DHT was found to be the principal intranuclear steroid.