View source for Pregnenolone

{{Distinguish|Pregnanolone|Pregneninolone}}
{{About|pregnenolone as a hormone|its use as a medication or supplement|Pregnenolone (medication)|other uses}}
{{Chembox
<!-- Images -->
| ImageFile = Pregnenolone.svg
| ImageSize = 235px
| ImageClass = skin-invert
| ImageFile2 = Pregnenolona3D.png
| ImageSize2 = 235px
<!-- Names -->
| IUPACName = 3β-Hydroxypregn-5-en-20-one
| SystematicName = 1-[(1''S'',3a''S'',3b''S'',7''S'',9a''R'',9b''S'',11a''S'')-7-Hydroxy-9a,11a-dimethyl-2,3,3a,3b,4,6,7,8,9,9a,9b,10,11,11a-tetradecahydro-1''H''-cyclopenta[''a'']phenanthren-1-yl]ethan-1-one
| OtherNames = P5; 5-Pregnenolone; δ<sup>5</sup>-Pregnene-3β-ol-20-one; Pregn-5-en-3β-ol-20-one; NSC-1616
<!-- Sections -->
| Section1 = {{Chembox Identifiers
| CASNo = 145-13-1
| ChEBI = 16581
| ChEMBL = 253363
| ChemSpiderID = 8611
| DrugBank = DB02789
| KEGG = C01953
| PubChem = 8955
| SMILES = CC(=O)[C@H]1CC[C@@H]2[C@@]1(CC[C@H]3[C@H]2CC=C4[C@@]3(CC[C@@H](C4)O)C)C
| StdInChI = 1S/C21H32O2/c1-13(22)17-6-7-18-16-5-4-14-12-15(23)8-10-20(14,2)19(16)9-11-21(17,18)3/h4,15-19,23H,5-12H2,1-3H3/t15-,16-,17+,18-,19-,20-,21+/m0/s1
| StdInChIKey = ORNBQBCIOKFOEO-QGVNFLHTSA-N
| UNII = 73R90F7MQ8
  }}
| Section2 = {{Chembox Properties
| C=21 | H=32 | O=2
| MolarMass = 316.485 g/mol
| Appearance = 
| Density = 
| MeltingPt = 193 °C
| BoilingPt = 
| Solubility = 
  }}
| Section3 = {{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
  }}
}}

'''Pregnenolone''' ('''P5'''), or '''pregn-5-en-3β-ol-20-one''', is an [[endogenous]] [[steroid]] and [[precursor (biochemistry)|precursor]]/[[metabolic intermediate]] in the [[biosynthesis]] of most of the [[steroid hormone]]s, including the [[progestogen]]s, [[androgen]]s, [[estrogen]]s, [[glucocorticoid]]s, and [[mineralocorticoid]]s.<ref name="pmid15415436">{{cite journal | vauthors = Henderson E, Weinberg M, Wright WA | title = Pregnenolone | journal = J. Clin. Endocrinol. Metab. | volume = 10 | issue = 4 | pages = 455–74 | date = April 1950 | pmid = 15415436 | doi = 10.1210/jcem-10-4-455 }}</ref> In addition, pregnenolone is [[biological activity|biologically active]] in its own right, acting as a [[neurosteroid]].<ref name="pmid21756978"/>

In addition to its role as a natural hormone, pregnenolone has been used as a [[medication]] and [[dietary supplement|supplement]]; for information on pregnenolone as a medication or supplement, see the [[pregnenolone (medication)]] article.

{{TOC limit|3}}

==Biological function==
Pregnenolone and its 3β-[[sulfate]], [[pregnenolone sulfate]], like [[dehydroepiandrosterone]] (DHEA), [[DHEA sulfate]], and [[progesterone]], belong to the group of [[neuroactive steroid|neurosteroid]]s that are found in high concentrations in certain areas of the brain, and are synthesized there. Neurosteroids affect synaptic functioning, are [[neuroprotective]], and enhance [[myelin]]ization. Pregnenolone and its sulfate ester may improve cognitive and [[memory]] function.<ref name="pmid11744095">{{cite journal |vauthors=Vallée M, Mayo W, Le Moal M | title = Role of pregnenolone, dehydroepiandrosterone and their sulfate esters on learning and memory in cognitive aging | journal = Brain Research. Brain Research Reviews | volume = 37 | issue = 1–3 | pages = 301–12 |date=November 2001 | pmid = 11744095 | doi = 10.1016/S0165-0173(01)00135-7| s2cid = 22186709 }}</ref> In addition, they may have protective effects against [[schizophrenia]].<ref name="pmid21756978">{{cite journal  |vauthors=Marx CE, Bradford DW, Hamer RM, etal | title = Pregnenolone as a novel therapeutic candidate in schizophrenia: emerging preclinical and clinical evidence | journal = Neuroscience | volume = 191 | pages = 78–90 |date=September 2011 | pmid = 21756978 | doi = 10.1016/j.neuroscience.2011.06.076 | s2cid = 26396652 }}</ref>

==Biological activity==

===Neurosteroid activity===
Pregnenolone is an allosteric [[endocannabinoid]], as it is a [[negative allosteric modulator]] of the [[CB1 receptor|CB<sub>1</sub> receptor]].<ref name="pmid26433186" /><ref name="Pertwee2015">{{Citation|last=Pertwee|first=Roger G.|date=2015|pages=1–37|publisher=Springer International Publishing|language=en|doi=10.1007/978-3-319-20825-1_1|pmid=26408156|isbn=9783319208244|title=Endocannabinoids|volume=231|series=Handbook of Experimental Pharmacology|chapter=Endocannabinoids and Their Pharmacological Actions}}</ref> Pregnenolone is involved in a natural [[negative feedback]] loop against CB<sub>1</sub> receptor activation in animals. It prevents CB<sub>1</sub> receptor [[agonist]]s like [[tetrahydrocannabinol]], the main active constituent in [[cannabis (drug)|cannabis]], from fully activating the CB<sub>1</sub>.<ref>Vallée, M., Vitiello, S., Bellocchio, L., Hébert-Chatelain, E., Monlezun, S., Martin-Garcia, E., Kasanetz, F., Baillie, GL., Panin, F., Cathala, A., Roullot-Lacarrière, V., Fabre, S., Hurst, DP., Lynch, DL., Shore, DM., Deroche-Gamonet, V., Spampinato, U., Revest, JM., Maldonado, R., Reggio, PH., Ross, RA., Marsicano, G., Piazza, PV. [https://www.researchgate.net/publication/259567046], "Pregnenolone Can Protect the Brain from Cannabis Intoxication", ''Science'', January 2014 Science 343(6166):94-8.</ref> A related compound [[AEF0117]] has been derived from pregnenolone and is more specific for this type of activity.

Pregnenolone has been found to bind with high, [[nanomolar]] [[affinity (pharmacology)|affinity]] to [[microtubule-associated protein 2]] (MAP2) in the brain.<ref name="pmid17651807">{{cite journal | vauthors = Mellon SH | title = Neurosteroid regulation of central nervous system development | journal = Pharmacol. Ther. | volume = 116 | issue = 1 | pages = 107–24 | year = 2007 | pmid = 17651807 | pmc = 2386997 | doi = 10.1016/j.pharmthera.2007.04.011 }}</ref><ref name="pmid16537405">{{cite journal | vauthors = Fontaine-Lenoir V, Chambraud B, Fellous A, David S, Duchossoy Y, Baulieu EE, Robel P | title = Microtubule-associated protein 2 (MAP2) is a neurosteroid receptor | journal = Proc. Natl. Acad. Sci. U.S.A. | volume = 103 | issue = 12 | pages = 4711–6 | year = 2006 | pmid = 16537405 | pmc = 1450236 | doi = 10.1073/pnas.0600113103 | bibcode = 2006PNAS..103.4711F | doi-access = free }}</ref> In contrast to pregnenolone, pregnenolone sulfate did not bind to [[microtubule]]s.<ref name="pmid17651807" /><ref name="pmid16537405" /> However, progesterone did and with similar affinity to pregnenolone, although unlike pregnenolone, it did not increase binding of MAP2 to [[tubulin]].<ref name="pmid17651807" /><ref name="pmid16537405" /> Pregnenolone was found to induce tubule polymerization in neuronal cultures and to increase [[neurite]] growth in PC12 cells treated with [[nerve growth factor]].<ref name="pmid17651807" /><ref name="pmid16537405" /> As such, pregnenolone may control formation and stabilization of microtubules in neurons and may affect both [[neural development]] during [[prenatal development]] and [[neural plasticity]] during [[aging]].<ref name="pmid17651807" /><ref name="pmid16537405" />

Although pregnenolone itself does not possess these activities, its [[metabolite]] [[pregnenolone sulfate]] is a [[negative allosteric modulator]] of the [[GABAA receptor|GABA<sub>A</sub> receptor]]<ref name="pmid3138576">{{cite journal |vauthors=Majewska MD, Mienville JM, Vicini S | title = Neurosteroid pregnenolone sulfate antagonizes electrophysiological responses to GABA in neurons | journal = Neuroscience Letters | volume = 90 | issue = 3 | pages = 279–84 |date=August 1988 | pmid = 3138576 | doi = 10.1016/0304-3940(88)90202-9| s2cid = 1101046 }}</ref> as well as a [[positive allosteric modulator]] of the [[NMDA receptor]].<ref name="pmid1654510">{{cite journal |vauthors=Wu FS, Gibbs TT, Farb DH | title = Pregnenolone sulfate: a positive allosteric modulator at the N-methyl-D-aspartate receptor | journal = Molecular Pharmacology | volume = 40 | issue = 3 | pages = 333–6 |date=September 1991 | pmid = 1654510 | url = http://molpharm.aspetjournals.org/cgi/pmidlookup?view=long&pmid=1654510}}</ref><ref name="pmid1387199">{{cite journal |vauthors=Irwin RP, Maragakis NJ, Rogawski MA, Purdy RH, Farb DH, Paul SM | title =  Pregnenolone sulfate augments NMDA receptor mediated increases in intracellular Ca2+ in cultured rat hippocampal neurons | journal = Neurosci Lett | volume = 141 | issue = 1 |pages = 30–4 | date = July 1992 |pmid =1387199 | doi=10.1016/0304-3940(92)90327-4| s2cid = 36972583 | url = https://zenodo.org/record/1258463 }}</ref> In addition, pregnenolone sulfate has been shown to activate the [[TRPM3|transient receptor potential M3]] (TRPM3) [[ion channel]] in [[hepatocyte]]s and [[Islets of Langerhans|pancreatic islet]]s causing [[calcium]] entry and subsequent [[insulin]] release.<ref name="pmid18978782">{{cite journal  |vauthors=Wagner TF, Loch S, Lambert S, etal | title = Transient receptor potential M3 channels are ionotropic steroid receptors in pancreatic beta cells | journal = Nature Cell Biology | volume = 10 | issue = 12 | pages = 1421–30 |date=December 2008 | pmid = 18978782 | doi = 10.1038/ncb1801 | s2cid = 19925356 }}</ref>

===Nuclear receptor activity===
Pregnenolone has been found to act as an [[agonist]] of the [[pregnane X receptor]].<ref name="pmid10548883">{{cite journal | vauthors = Kliewer SA, Lehmann JM, Milburn MV, Willson TM | title = The PPARs and PXRs: nuclear xenobiotic receptors that define novel hormone signaling pathways | journal = Recent Prog. Horm. Res. | volume = 54 | pages = 345–67; discussion 367–8 | year = 1999 | pmid = 10548883 }}</ref>

Pregnenolone has no [[progestogen]]ic, [[corticosteroid]], [[estrogen]]ic, [[androgen]]ic, or [[antiandrogen]]ic activity.<ref name="pmid15415436" />

==Biochemistry==
[[File:Steroidogenesis.svg|right|thumb|450px|[[Steroidogenesis]], showing pregnenolone near top left]]

===Biosynthesis===
Pregnenolone is [[biosynthesis|synthesized]] from [[cholesterol]]. This [[biotransformation|conversion]] involves [[hydroxylation]] of the [[side chain]] at the C20 and C22 positions, with [[bond cleavage|cleavage]] of the [[side chain]]. The [[enzyme]] performing this task is [[P450scc|cytochrome P450scc]], located in the [[mitochondria]],<ref name="1981-Hanukoglu-2">{{cite journal |vauthors=Hanukoglu I, Spitsberg V, Bumpus JA, Dus KM, Jefcoate CR |title=Adrenal mitochondrial cytochrome P-450scc. Cholesterol and Adirondacks interactions at equilibrium and during turnover |journal=J Biol Chem |volume=256 |issue=9 |pages=4321–8 |date=May 1981 |pmid=7217084 |doi=10.1016/S0021-9258(19)69436-6 |url=|doi-access=free }}</ref> and controlled by [[anterior pituitary]] [[trophic hormone]]s, such as [[adrenocorticotropic hormone]], [[follicle-stimulating hormone]], and [[luteinizing hormone]], in the [[adrenal gland]]s and [[gonad]]s.<ref name="1990-Hanukoglu">{{cite journal |vauthors=Hanukoglu I, Feuchtwanger R, Hanukoglu A |title=Mechanism of corticotropin and cAMP induction of mitochondrial cytochrome P450 system enzymes in adrenal cortex cells |journal=J Biol Chem |volume=265 |issue=33 |pages=20602–8 |date=November 1990 |pmid=2173715 |doi=10.1016/S0021-9258(17)30545-8 |doi-access=free |url=}}</ref> There are two [[metabolic intermediate|intermediate]]s in the transformation of cholesterol into pregnenolone, [[22R-hydroxycholesterol|22''R''-hydroxycholesterol]] and [[20α,22R-dihydroxycholesterol|20α,22''R''-dihydroxycholesterol]], and all three steps in the transformation are catalyzed by P450scc.<ref name="LemkeWilliams2008">{{cite book|author1=Thomas L. Lemke|author2=David A. Williams|title=Foye's Principles of Medicinal Chemistry|url=https://books.google.com/books?id=R0W1ErpsQpkC&pg=PA883|year=2008|publisher=Lippincott Williams & Wilkins|isbn=978-0-7817-6879-5|pages=883–}}</ref> Pregnenolone is produced mainly in the [[adrenal gland]]s, the [[gonad]]s, and the [[brain]].<ref name="pmid26433186">{{cite journal | vauthors = Vallée M | title = Neurosteroids and potential therapeutics: Focus on pregnenolone | journal = J. Steroid Biochem. Mol. Biol. | volume = 160 | pages = 78–87 | year = 2016 | pmid = 26433186 | doi = 10.1016/j.jsbmb.2015.09.030 | s2cid = 3468546 }}</ref> Although pregnenolone is also produced in the gonads and brain, most circulating pregnenolone is derived from the [[adrenal cortex]].<ref name="QuestDiagnostics">{{Cite web |title=The Quest Diagnostics Manual. Endocrinology. Test Selection and Interpretation. Fourth Edition |url=https://docplayer.net/86293048-The-quest-diagnostics-manual-endocrinology-test-selection-and-interpretation-fourth-edition.html |access-date=15 September 2023 |website=docplayer.net |page=152}}</ref>

To assay conversion of cholesterol to pregnenolone, radiolabeled cholesterol has been used.<ref name="HanukogluJefcoate1980">{{cite journal|vauthors=Hanukoglu I, Jefcoate CR | title = Pregnenolone separation from cholesterol using Sephadex LH-20 mini-columns | journal = Journal of Chromatography A | year = 1980 | volume = 190 | issue = 1 | pages = 256–262 | doi = 10.1016/S0021-9673(00)85545-4 | url = https://zenodo.org/record/890904 }}</ref> Pregnenolone product can be separated from cholesterol substrate using Sephadex LH-20 minicolumns.<ref name="HanukogluJefcoate1980" />

===Distribution===
Pregnenolone is [[lipophilic]] and readily crosses the [[blood–brain barrier]].<ref name="pmid23348009">{{cite journal | vauthors = Sripada RK, Marx CE, King AP, Rampton JC, Ho SS, Liberzon I | title = Allopregnanolone elevations following pregnenolone administration are associated with enhanced activation of emotion regulation neurocircuits | journal = Biol. Psychiatry | volume = 73 | issue = 11 | pages = 1045–53 | year = 2013 | pmid = 23348009 | pmc = 3648625 | doi = 10.1016/j.biopsych.2012.12.008 }}</ref> This is in contrast to [[pregnenolone sulfate]], which does not cross the blood–brain barrier.<ref name="RhoSankar2010">{{cite book|author1=Jong Rho|author2=Raman Sankar|author3=Carl E. Stafstrom|title=Epilepsy: Mechanisms, Models, and Translational Perspectives|url=https://books.google.com/books?id=8prMBQAAQBAJ&pg=PA479|date=18 June 2010|publisher=CRC Press|isbn=978-1-4200-8560-0|pages=479–}}</ref><ref name="Symposium2008">{{cite book|author=CIBA Foundation Symposium|title=Steroids and Neuronal Activity|url=https://books.google.com/books?id=KeZlL3XbmQsC&pg=PA101|date=30 April 2008|publisher=John Wiley & Sons|isbn=978-0-470-51399-6|pages=101–}}</ref>

===Metabolism===
Pregnenolone undergoes further steroid [[metabolism]] in one of several ways:

* Pregnenolone can be converted into [[progesterone]]. The critical enzyme step is two-fold using a [[3β-hydroxysteroid dehydrogenase]] and a [[delta 5-4 isomerase|Δ<sup>5-4</sup> isomerase]]. The latter transfers the [[double bond]] from C5 to C4 on the A ring.  Progesterone is the entry into the Δ<sup>4</sup> pathway, resulting in production of [[17α-hydroxyprogesterone]] and [[androstenedione]], precursor to [[testosterone]] and [[estrone]]. [[Aldosterone]] and [[corticosteroid]]s are also derived from progesterone or its derivatives.
* Pregnenolone can be converted to [[17α-hydroxypregnenolone]] by the enzyme 17α-hydroxylase ([[CYP17A1]]). Using this pathway, termed Δ<sup>5</sup> pathway, the next step is conversion to [[dehydroepiandrosterone]] (DHEA) via 17,20-lyase (CYP17A1). DHEA is the precursor of androstenedione.
* Pregnenolone can be converted to [[androstadienol]] by 16-ene synthase (CYP17A1).
* Pregnenolone can be converted to [[pregnenolone sulfate]] by [[steroid sulfotransferase]], and this conversion can be reversed by [[steroid sulfatase]].

===Levels===
Normal circulating levels of pregnenolone are as follows:<ref name="QuestDiagnostics" />

* Men: 10 to 200&nbsp;ng/dL
* Women: 10 to 230&nbsp;ng/dL
* Children: 10 to 48&nbsp;ng/dL
* Adolescent boys: 10 to 50&nbsp;ng/dL
* Adolescent girls: 15 to 84&nbsp;ng/dL

Mean levels of pregnenolone have been found not to significantly differ in postmenopausal women and elderly men (40 and 39&nbsp;ng/dL, respectively).<ref name="pmid6274897">{{cite journal | vauthors = Vermeulen A, Deslypere JP, Schelfhout W, Verdonck L, Rubens R | title = Adrenocortical function in old age: response to acute adrenocorticotropin stimulation | journal = J. Clin. Endocrinol. Metab. | volume = 54 | issue = 1 | pages = 187–91 | date = January 1982 | pmid = 6274897 | doi = 10.1210/jcem-54-1-187 }}</ref>

Studies have found that pregnenolone levels are not significantly changed after [[surgical castration|surgical]] or [[medical castration]] in men, which is in accordance with the fact that pregnenolone is mainly derived from the adrenal glands.<ref name="VickeryNestor2012">{{cite book|author1=B.H. Vickery|author2=J.J. Nestor|author3=E.S. Hafez|title=LHRH and Its Analogs: Contraceptive and Therapeutic Applications|url=https://books.google.com/books?id=am3yCAAAQBAJ&pg=PA341|date=6 December 2012|publisher=Springer Science & Business Media|isbn=978-94-009-5588-2|pages=341–|quote=On the other hand there were no significant changes in serum levels of the steroid precursors pregnenolone and progesterone. [...] Unchanged levels of pregnenolone, in the presence of decreased 17α-OH-progesterone and testosterone concentrations, suggest that a block of 17-hydroxylase and 17,20-desmolase activity takes place in the human testis.}}</ref><ref name="pmid6086697">{{cite journal | vauthors = Bélanger A, Dupont A, Labrie F | title = Inhibition of basal and adrenocorticotropin-stimulated plasma levels of adrenal androgens after treatment with an antiandrogen in castrated patients with prostatic cancer | journal = J. Clin. Endocrinol. Metab. | volume = 59 | issue = 3 | pages = 422–6 | date = September 1984 | pmid = 6086697 | doi = 10.1210/jcem-59-3-422 }}</ref><ref name="pmid6800852">{{cite journal | vauthors = Faure N, Labrie F, Lemay A, Bélanger A, Gourdeau Y, Laroche B, Robert G | title = Inhibition of serum androgen levels by chronic intranasal and subcutaneous administration of a potent luteinizing hormone-releasing hormone (LH-RH) agonist in adult men | journal = Fertil. Steril. | volume = 37 | issue = 3 | pages = 416–24 | date = March 1982 | pmid = 6800852 | doi = 10.1016/S0015-0282(16)46107-8 | doi-access = free }}</ref> Conversely, medical castration has been found to partially suppress pregnenolone levels in premenopausal women.<ref name="pmid2199228">{{cite journal | vauthors = Dupont A, Dupont P, Belanger A, Mailoux J, Cusan L, Labrie F | title = Hormonal and biochemical changes during treatment of endometriosis with the luteinizing hormone-releasing hormone (LH-RH) agonist [D-Trp6,des-Gly-NH2(10)]LH-RH ethylamide | journal = Fertil. Steril. | volume = 54 | issue = 2 | pages = 227–32 | date = August 1990 | pmid = 2199228 | doi = 10.1016/S0015-0282(16)53694-2 | doi-access = free }}</ref><ref name="pmid3116031">{{cite journal | vauthors = Steingold K, De Ziegler D, Cedars M, Meldrum DR, Lu JK, Judd HL, Chang RJ | title = Clinical and hormonal effects of chronic gonadotropin-releasing hormone agonist treatment in polycystic ovarian disease | journal = J. Clin. Endocrinol. Metab. | volume = 65 | issue = 4 | pages = 773–8 | date = October 1987 | pmid = 3116031 | doi = 10.1210/jcem-65-4-773 }}</ref> Similarly, an [[adrenalectomy|adrenalectomized]] premenopausal woman showed incompletely diminished circulating pregnenolone levels.<ref name="pmid4270264">{{cite journal | vauthors = Abraham GE, Chakmakjian ZH | title = Serum steroid levels during the menstrual cycle in a bilaterally adrenalectomized woman | journal = J. Clin. Endocrinol. Metab. | volume = 37 | issue = 4 | pages = 581–7 | date = October 1973 | pmid = 4270264 | doi = 10.1210/jcem-37-4-581 }}</ref>

==Chemistry==
{{See also|List of neurosteroids}}

Pregnenolone is also known chemically as pregn-5-en-3β-ol-20-one.<ref name="Elks2014">{{cite book|author=J. Elks|title=The Dictionary of Drugs: Chemical Data: Chemical Data, Structures and Bibliographies|url=https://books.google.com/books?id=0vXTBwAAQBAJ&pg=PA665|date=14 November 2014|publisher=Springer|isbn=978-1-4757-2085-3|pages=665–}}</ref><ref name="IndexNominum2000">{{cite book|title=Index Nominum 2000: International Drug Directory|url=https://books.google.com/books?id=5GpcTQD_L2oC&pg=PA872|year=2000|publisher=Taylor & Francis|isbn=978-3-88763-075-1|pages=872–873}}</ref> Like other [[steroid]]s, it consists of four interconnected [[cyclic hydrocarbon]]s.<ref name="Elks2014" /><ref name="IndexNominum2000" /> The compound contains [[ketone]] and [[hydroxyl]] [[functional group]]s, two [[methyl]] branches, and a [[double bond]] at C5, in the B cyclic hydrocarbon ring.<ref name="Elks2014" /><ref name="IndexNominum2000" /> Like many steroid hormones, it is [[hydrophobic]]. The [[sulfated]] derivative, [[pregnenolone sulfate]], is water-soluble.

[[3β-Dihydroprogesterone]] (pregn-4-en-3β-ol-20-one) is an [[isomer]] of pregnenolone in which the C5 [[double bond]] has been replaced with a C4 double bond.<ref name="pmid15415436" />

==History==
Pregnenolone was first [[chemical synthesis|synthesized]] by [[Adolf Butenandt]] and colleagues in 1934.<ref>{{cite journal |last1=Butenandt |first1=Adolf |last2=Westphal |first2=Ulrich |last3=Cobler |first3=Heinz |title=Über einen Abbau des Stigmasterins zu corpus-luteum-wirksamen Stoffen; ein Beitrag zur Konstitution des Corpusluteum-Hormons (Vorläuf. Mitteil.) |journal=Berichte der Deutschen Chemischen Gesellschaft (A and B Series) |date=12 September 1934 |volume=67 |issue=9 |pages=1611–1616 |doi=10.1002/cber.19340670931}}</ref>

==References==
{{Reflist}}

{{Endogenous steroids}}
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[[Category:Sterols]]
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[[Category:Ketones]]
[[Category:Neurosteroids]]
[[Category:Pregnane X receptor agonists]]
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