title: Effects of castration on androstenedione, testosterone and dihydrotestosterone plasma levels in adult male rats.
abstract: In the present study we investigated the effects of castration on androstenedione (A), testosterone (T) and dihydrotestosterone (DHT) plasma levels in adult male rats 5 and 47 days after castration. In another group of 60-day-old castrated rats, the three steroids have been evaluated during testosterone propionate administration. Our data show that 5 days after orchiectomy all three steroids were significantly decreased (p less than 0.001) with respect to control values. 47 days after orchiectomy, T and DHT were also significantly decreased with respect to the control group. In both groups of orchiectomized rats the A/T ratio increased significantly with respect to controls. On the contrary, the T/DHT ratio sharply decreased. This suggests that DHT, in orchiectomized rats, could derive from precursors other than T. A negative correlation between A and the T/DHT ratio was observed 47 days after castration in adult animals and emphasized upon testosterone propionate administration. In the latter group, T was significantly lower while A is significantly augmented with respect to control values. Finally, the above-mentioned negative correlation indicates a possible prevalent role of A in contributing to the circulating levels of DHT in adult orchiectomized rats.
mesh_terms: D000735:Androstenedione / Q000097:blood*; D000818:Animals; D013196:Dihydrotestosterone / Q000097:blood*; D008297:Male; D009919:Orchiectomy; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013739:Testosterone / Q000097:blood*
chemical_list: D013196:Dihydrotestosterone; D013739:Testosterone; D000735:Androstenedione