Steroid 4-Androstenedione with CAS No: 63-05-8
|Synonyms||4-AD;4-Androstene-3,17-dione; 4-androstenedione; Androst-4-ene-3,17-dione; ; androst-4-ene-3,17-dione|
|Appearance||White crystalline powder|
4-Androstenedione is the common precursor of male and female sex hormones. Some 4-Androstenedione is also secreted into the plasma, and may be converted in peripheral tissues to testosterone and estrogens.
4-Androstenedione can be synthesized in one of two ways. The primary pathway involves conversion of 17-hydroxypregnenolone to dehydroepiandrosterone by way of 17,20-lyase, with subsequent conversion of dehydroepiandrosterone to 4-Androstenedione via the enzyme 3-β-hydroxysteroid dehydrogenase. The secondary pathway involves conversion of 17-hydroxyprogesterone, most often a precursor to cortisol, to 4-androstenedione directly by way of 17,20-lyase. Thus, 17,20-lyase is required for the synthesis of 4-androstenedione, whether immediately or one step removed.
The production of adrenal 4-Androstenedione is governed by ACTH, whereas production of gonadal 4-Androstenedione is under control by gonadotropins. In premenopausal women, the adrenal glands and ovaries each produce about half of the total 4-androstenedione(about 3 mg/day). After menopause, 4-androstenedione production is about halved, due primarily to the reduction of the steroid secreted by the ovary. Nevertheless, 4-androstenedione is the principal steroid produced by the postmenopausal ovary.