Formation in Vitro of 5a-Dihydrotestosterone and other 5a-Reduced Metabolites of3H-Testosterone by the Seminiferous Tubules and Interstitial Tissue from Immature and Mature Rat Testes1
Testes of 13 immature and mature rats were separated into seminiferous tubules and interstitial tissue and incubated with 3H-testosterone (T) and an NADPH generating system. The per unit tissue wt conversion to 3H-5α-dihydrotestosterone (DHT) by incubated tubules from mature rats was much higher than that by incubated interstitial tissue. Both tissue components left more than 85% of the 3H-T substrate unconverted and total α-reduction of 3H-T was similar in both tubules and interstitial tissue. Interstitial tissue from testes of immature rats, however, converted more 3H-T to 3H-DHT than the testicular tubules and total 5α-reduction of T by the Leydig cells was 20 times greater than that of the tubules. (Endocrinology92: 6, 1973)