Testosterone is the primary male sex hormone and androgen in males. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. It is associated with increased aggression, sex drive, the inclination to impress partners and other courting behaviors. In addition, testosterone in both sexes is involved in health and well-being, where it has a significant effect on overall mood, cognition, social and sexual behavior, metabolism and energy output, the cardiovascular system, and in the prevention of osteoporosis. Insufficient levels of testosterone in men may lead to abnormalities including frailty, accumulation of adipose fat tissue within the body, anxiety and depression, sexual performance issues, and bone loss.
An androgen is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes the embryological development of the primary male sex organs, and the development of male secondary sex characteristics at puberty. Androgens are synthesized in the testes, the ovaries, and the adrenal glands.
Dihydrotestosterone is an endogenous androgen sex steroid and hormone primarily involved in the growth and repair of the prostate, the production of sebum, and body hair composition.
Fluoxymesterone, sold under the brand names Halotestin and Ultandren among others, is an androgen and anabolic steroid (AAS) medication which is used in the treatment of low testosterone levels in men, delayed puberty in boys, breast cancer in women, and anemia. It is taken by mouth.
Trestolone, also known as 7α-methyl-19-nortestosterone (MENT), is an experimental androgen/anabolic steroid (AAS) and progestogen medication which has been under development for potential use as a form of hormonal birth control for men and in androgen replacement therapy for low testosterone levels in men but has never been marketed for medical use. It is given as an implant that is placed into fat. As trestolone acetate, an androgen ester and prodrug of trestolone, the medication can also be given by injection into muscle.
Adrenosterone, also known as Reichstein's substance G , as well as 11-ketoandrostenedione (11-KA4), 11-oxoandrostenedione (11-OXO), and androst-4-ene-3,11,17-trione, is a steroid hormone with an extremely weak androgenic effect, and an intermediate/prohormone of 11-ketotestosterone. It was first isolated in 1936 from the adrenal cortex by Tadeus Reichstein at the Pharmaceutical Institute in the University of Basel. Originally, adrenosterone was called Reichstein's substance G. Adrenosterone occurs in trace amounts in humans as well as most mammals and in larger amounts in fish, where it is a precursor to the primary androgen, 11-ketotestosterone.
Anabolic steroids, also known as anabolic-androgenic steroids (AAS), are a class of drugs that are structurally related to testosterone, the main male sex hormone, and produce effects by binding to the androgen receptor. Anabolic steroids have a number of medical uses, but are also used by athletes to increase muscle size, strength, and performance.
Formebolone, also known as formyldienolone, as well as 2-formyl-11α-hydroxy-17α-methyl-δ1-testosterone, is an orally active anabolic-androgenic steroid (AAS) described as an anticatabolic and anabolic drug that is or has been marketed in Spain and Italy. As an AAS, it shows some anabolic activity, though it is inferior to testosterone in terms of potency, but is said to have virtually no androgenic activity. Formebolone counteracts the catabolic effects of potent glucocorticoids like dexamethasone phosphate. A close analogue, roxibolone, shows similar antiglucocorticoid activity to formebolone but, in contrast, is devoid of activity as an AAS.
Testosterone undecanoate, sold under the brand names Andriol, Aveed and Nebido among others, is an androgen and anabolic steroid (AAS) medication that is used mainly in the treatment of low testosterone levels in men, It is taken by mouth or given by injection into muscle.
Androgen deficiency is a medical condition characterized by insufficient androgenic activity in the body. Androgen deficiency most commonly affects women, and is also called Female androgen insufficiency syndrome (FAIS), although it can happen in both sexes. Androgenic activity is mediated by androgens, and is dependent on various factors including androgen receptor abundance, sensitivity and function. Androgen deficiency is associated with lack of energy and motivation, depression, lack of desire (libido), and in more severe cases changes in secondary sex characteristics.
Dimethandrolone (DMA), also known by its developmental code name CDB-1321, is an experimental androgen/anabolic steroid (AAS) and progestogen medication which is under investigation for potential clinical use.
Dimethandrolone undecanoate (DMAU), also known by its developmental code name CDB-4521, is an experimental androgen/anabolic steroid (AAS) and progestogen medication which is under development as a potential birth control pill for men. It is taken by mouth, but can also be given by injection into muscle.
11β-Methyl-19-nortestosterone 17β-dodecylcarbonate (11β-MNTDC) is a synthetic and orally active anabolic–androgenic steroid (AAS) and a derivative of nandrolone (19-nortestosterone) which was developed by the Contraceptive Development Branch (CDB) of the National Institute of Child Health and Human Development (NICHD) and has not been marketed for medical use at this time. It is an androgen ester – specifically, the C17β dodecylcarbonate ester of 11β-methyl-19-nortestosterone (11β-MNT) – and acts as a prodrug of 11β-MNT in the body.
11β-Methyl-19-nortestosterone (11β-MNT) is a synthetic and orally active anabolic–androgenic steroid (AAS) and a derivative of nandrolone (19-nortestosterone) which was developed by the Contraceptive Development Branch (CDB) of the National Institute of Child Health and Human Development (NICHD) and has not been marketed at this time.
11β-Hydroxyandrostenedione (11β-OHA4), also known as 11β-hydroxyandrost-4-ene-3,17-dione, is an endogenous, naturally occurring steroid and androgen prohormone that is produced primarily, if not exclusively, in the adrenal glands. It is closely related to adrenosterone, 11-ketotestosterone (11-KT), and 11-ketodihydrotestosterone (11-KDHT), which are also produced in the adrenal glands.
11-Ketodihydrotestosterone (11-KDHT), also known as 5α-androstan-17β-ol-3,11-dione, is an endogenous, naturally occurring steroid and androgen prohormone that is produced primarily, if not exclusively, in the adrenal glands. It is closely related to 11β-hydroxyandrostenedione (11β-KA4), adrenosterone, and 11-ketotestosterone (11-KT), which are also produced in the adrenal glands.
Reproduction and vocalization in midshipman fish are closely interlinked. Mating in midshipman fish depends on auditory communication, the production and reception of sound signals. Males produce several different vocalizations, while females only make grunts in non-breeding situations.
The androgen backdoor pathway is a collective name for all metabolic pathways where clinically relevant androgens are synthesized from 21-carbon steroids (pregnanes) by their 5α-reduction, bypassing testosterone and/or androstenedione.
11-Ketoandrosterone is an endogenous steroid.
11β-Hydroxytestosterone is an endogenous steroid, a metabolite of testosterone. Although it may not have significant androgenic activity, it may still be an important precursor to androgenic molecules.
