Abstract
Plasma levels of dehydroepiandrosterone (DHA), dehydroepiandrosterone sulfate (DHA-S) androstenedione (Δ 4A), androsterone (5 α -A) and androstanediol (5 α -Ad) levels were measured by specific radioimmunoassay in pubertal girls to elucidate the physiological role of these hormones on female sexual development. One hundred twenty girls between ages 6 and 17 were selected for this study. Blood samples were collected into tubes containing 1W/V % EDTA and immediately centrifuged. Steroids in plasma were extracted and separated with a Sephadex LH-20 column. RIA was applied using a specific antibody for each steroid. Plasma DHA levels increased from age 8 followed by a significant increase between ages 10 and 11. DHA-S levels in plasma started to increase earlier than DHA. Plasma Δ 4A levels before menarche showed no significant change until age 10, and gradually increased after menarche. Plasma 5 α -A levels started to increase from age 9 and reached maximum levels at age 17. On the other hand, plasma 5 α -Ad levels before menarche were higher than after menarche. There was a significant decrease in 5 α -Ad levels between ages 11 and 12. Changes of plasma androgen levels in puberty were studied. This is the first report demonstrating the changes of 5 α -Ad levels in pubertal girls. A significant decrease of 5 α -Ad suggested that this steroid plays an important role in the initiation of menarche.
