17α-Hydroxypregnenolone

Pharmacokinetic data
Metabolism	Adrenal, Gonads
Identifiers
IUPAC name 3β,17α-dihydroxypregn-5-en-20-one
CAS Number	387-79-1 Y
PubChem CID	3032570
ChemSpider	17215939 Y
UNII	77ME40334S
ChEBI	CHEBI:28750 N
CompTox Dashboard (EPA)	DTXSID20894988
ECHA InfoCard	100.006.239
Chemical and physical data
Formula	C21H32O3
Molar mass	332.484 g·mol−1
3D model (JSmol)	Interactive image
Melting point	268 °C (514 °F)
SMILES CC[C@@]2(O)CC[C@H]1[C@@H]3CCC4CC(O)C(=O)C[C@]4(C)[C@H]3CC[C@@]12C
InChI InChI=1S/C21H34O3/c1-4-21(24)10-8-16-14-6-5-13-11-17(22)18(23)12-19(13,2)15(14)7-9-20(16,21)3/h13-17,22,24H,4-12H2,1-3H3/t13?,14-,15+,16+,17?,19+,20+,21-/m1/s1 Y Key:QPLFSAZMHUAMKE-FOCOMJRBSA-N Y
NY (what is this?)  (verify)

17α-Hydroxypregnenolone is a pregnane (C21) steroid that is obtained by hydroxylation of pregnenolone at the C17α position. This step is performed by the mitochondrial cytochrome P450 enzyme 17α-hydroxylase (CYP17A1) that is present in the adrenal and gonads. Peak levels are reached in humans at the end of puberty and then decline.^[1] High levels are also achieved during pregnancy. It is also a known neuromodulator.

17α-Hydroxypregnenolone is considered a prohormone in the formation of dehydroepiandrosterone (DHEA), itself a prohormone of the sex steroids.

This conversion is mediated by the enzyme 17,20 lyase. As such 17α-hydroxypregenolone represents an intermediary in the Δ⁵ pathway that leads from pregnenolone to DHEA. 17α-Hydroxypregneolone is also converted to 17α-hydroxyprogesterone, a prohormone for glucocorticosteroids and androstenedione through the activity of 3α-hydroxysteroid dehydrogenase.

Measurements of 17α-hydroxypregnenolone are useful in the diagnosis of certain forms of congenital adrenal hyperplasia.^[2] In patients with congenital adrenal hyperplasia due to 3β-hydroxysteroid dehydrogenase deficiency 17α-hydroxypregnenolone is increased, while in patients with congenital adrenal hyperplasia due to 17α-hydroxylase deficiency levels are low to absent.

17α-hydroxypregnenolone is a known neuromodulator as its acts in the central nervous system. Specifically, it is known to modulate locomotion.^[3]

• Congenital adrenal hyperplasia
• Narave pig, intersex pigs that have low levels of 17α-Hydroxypregnenolone

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  Steroidogenesis