Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates by binding to androgen receptors. This includes the activity of the accessory male sex organs and development of male secondary sex haracteristics. Androgens, which were first discovered in 1936, are also called androgenic hormones or testoids. Androgens are also the original anabolic steroids. They are also the precursor of all estrogens, the female sex hormones. The primary and most well-known androgen is testosterone. A subset of androgens, adrenal androgens, includes any of the 19-carbon steroids synthesized
by the adrenal cortex, the outer portion of the adrenal gland (zonula reticularis - innermost region of the adrenal cortex), that function as weak steroids or steroid precursors, including dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate
(DHEA-S), and androstenedione.Besides testosterone, other androgens include:
- Dehydroepiandroster (DHEA): a steroid hormone produced in the adrenal cortex from cholesterol. It is the primary precursor of natural estrogens.
- Androstenedione (Andro): an androgenic steroid produced by the testes, adrenal cortex, and ovaries. While androstenediones are converted metabolically to testosterone and other androgens, they are also the parent structure of estrone.
- Androstenediol and androstanediolglucuronide: steroid metabolites that is thought to act as the main regulator of gonadotropin secretion
- Androsterone: a chemical by-product created during the breakdown of androgens, or derived from progesterone, that also exerts minor masculinising effects, but with one-seventh the intensity of testosterone. It is found in approximately equal amounts in the plasma and urine of both males and females.
- Dihydrotestosterone (DHT): a metabolite of testosterone, and a more potent androgens than testosterone in that it binds more strongly to androgen receptors. It is produced in the adrenal cortex.