Serum Testosterone and Dihydrotestosterone Levels Following Orchiectomy in the Adult Rat

Abstract

Serum concentration of testosterone (T) in 24 normal adult male rats, expressed as mean ± SD, was 5.5 ± 2.7 ng/ml. In the same animals mean dihydrotestosterone (DHT) was 0.35 ± 0.18 ng/ml. Within 5 min after orchiectomy, serum T concentration had decreased to 55.5% of the initial "control" value. Within 2 hr after orchiectomy serum T was undetectable (less than 0.06 ng/ml) in 4 of 6 animals. Twenty—four hr after orchiectomy, serum T was undetectable in 7 of 8 animals. Serum DHT concentrations decreased similarly after orchiectomy. (Endocrinology92: 1579, 1973)