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| Names | |
|---|---|
| IUPAC name 20α-Hydroxypregn-4-en-3-one | |
| Systematic IUPAC name (1S,3aS,3bS,9aR,9bS,11aS)-1-[(1S)-1-Hydroxyethyl]-9a,11a-dimethyl-1,2,3,3a,3b,4,5,8,9,9a,9b,10,11,11a-tetradecahydro-7H-cyclopenta[a]phenanthren-7-one | |
| Other names 20α-DHP; 20α-Hydroxyprogesterone; 20α-OHP; Pregn-4-en-20α-ol-3-one | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider | |
| EC Number |
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| MeSH | 20-alpha-Dihydroprogesterone |
| UNII | |
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| Properties | |
| C21H32O2 | |
| Molar mass | 316.478 g/mol |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
20α-Dihydroprogesterone (20α-DHP), also known as20α-hydroxyprogesterone (20α-OHP), is anaturally occurring,endogenousprogestogen.[1][2][3] It is ametabolite ofprogesterone, formed by the20α-hydroxysteroid dehydrogenases (20α-HSDs)AKR1C1,AKR1C2, andAKR1C3 and the17β-hydroxysteroid dehydrogenase (17β-HSD)HSD17B1.[4][5] 20α-DHP can be transformed back into progesterone by 20α-HSDs and by the 17β-HSDHSD17B2.[6][7] HSD17B2 is expressed in the humanendometrium andcervix among other tissues.[8][9][10][7] In animal studies, 20α-DHP has been found to be selectively taken up into and retained in targettissues such as theuterus,brain, andskeletal muscle.[6]
20α-DHP has very lowaffinity for theprogesterone receptor and is much lesspotent as a progestogen in comparison to progesterone, with about one-fifth of the relative progestogenic activity.[1][2][3][11][12][6][13] It has also been found to act as anaromatase inhibitor and to inhibit the production ofestrogen inbreast tissuein vitro.[14]
A single 200-mg oral dose of micronized progesterone has been found to result in peak levels of 20α-DHP of around 1 ng/mL after 2 hours.[15] In another study however, peak levels of 20α-DHP were around 10 ng/mL during therapy with 300 mg/day oral micronized progesterone.[16] 20α-DHP is formed from progesterone in theliver and in target tissues such as theendometrium.[16] It appears to be more slowly eliminated than progesterone.[16]
Levels of 5α-DHP have been quantified.[17]
In addition to progesterone, 20α- and 20β-hydroxyprogesterone (20α- and 20β-hydroxy-4-pregnene-3-one) also are found. These compounds have about one-fifth the progestational activity of progesterone in humans and other species.
