5β-Dihydrotestosterone (5β-DHT), also known as 5β-androstan-17β-ol-3-one or as etiocholan-17β-ol-3-one, is an

etiocholane Etiocholane, also known as 5β-androstane or 5-epiandrostane, is an androstane (C19) steroid. It is the 5β-isomer of androstane. Etiocholanes include 5β-androstanedione, 5β-dihydrotestosterone, 3α,5β-androstanediol, 3β,5β-androstanediol, ...

(5β-

androstane Androstane is a C19 steroidal hydrocarbon with a gonane core. Androstane can exist as either of two isomers, known as 5α-androstane and 5β-androstane. File:androstane.png, 5α-Androstane File:androstane 5beta.png, 5β-Androstane Pharmacology ...

)

steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...

as well as an inactive

metabolite In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...

testosterone Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testes and prostate, as well as promoting secondar ...

formed by 5β-reductase in the

liver The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for ...

and

bone marrow Bone marrow is a semi-solid tissue found within the spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It is composed of hematopoietic ce ...

and an intermediate in the formation of 3α,5β-androstanediol and 3β,5β-androstanediol (by 3α- and 3β-hydroxysteroid dehydrogenase) and, from them, respectively,

etiocholanolone Etiocholanolone, also known as 5β-androsterone, as well as 3α-hydroxy-5β-androstan-17-one or etiocholan-3α-ol-17-one, is an etiocholane (5β-androstane) steroid as well as an endogenous 17-ketosteroid that is produced from the metabolism of ...

and

epietiocholanolone Epietiocholanolone, also known as 3β-hydroxy-5β-androstan-17-one or as etiocholan-3β-ol-17-one, is an etiocholane (5β-androstane) steroid as well as an inactive metabolite of testosterone that is formed in the liver. The metabolic pathway i ...

(by

17β-hydroxysteroid dehydrogenase A hydroxysteroid is a molecule derived from a steroid with a hydrogen replaced with a hydroxy group. When the hydroxy group is specifically at the C3 position, hydroxysteroids are referred to as sterols, with an example being cholesterol. See ...

). Unlike its

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

5α-dihydrotestosterone (5α-DHT or simply DHT), 5β-DHT either does not bind to or binds only very weakly to the

androgen receptor The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone in th ...

. 5β-DHT is notable among metabolites of testosterone in that, due to the fusion of the A and B rings in the ''cis'' orientation, it has an extremely angular molecular shape, and this could be related to its lack of

androgen An androgen (from Greek ''andr-'', the stem of the word meaning "man") is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This inc ...

ic activity. 5β-DHT, unlike 5α-DHT, is also inactive in terms of

neurosteroid Neurosteroids, also known as neuroactive steroids, are endogenous or exogenous steroids that rapidly alter neuronal excitability through interaction with ligand-gated ion channels and other cell surface receptors. The term ''neurosteroid'' was coin ...

activity, although its metabolite, etiocholanolone, does possess such activity.

References

{{DEFAULTSORT:Dihydrotestosterone, 5β- Etiocholanes Human metabolites

See also

References