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P2016

Sigma-Aldrich

3α,21-Dihydroxy-5α-pregnan-20-one

≥95%

Synonym(s):

21-Hydroxyallopregnanolone, 5α-Pregnane-3α,21-diol-20-one, 5α-THDOC, Allopregnane-3α,21-diol-20-one, Allotetrahydrodeoxycorticosterone

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About This Item

Empirical Formula (Hill Notation):
C21H34O3
CAS Number:
567-02-2
Molecular Weight:
334.49
EC Number:
209-300-8
MDL number:
MFCD00051144
UNSPSC Code:
12352200
PubChem Substance ID:
24278624
NACRES:
NA.77

Quality Level

200

Assay

≥95%

form

powder

SMILES string

[H][C@@]12CC[C@@]3([H])[C@]4([H])CC[C@H](C(=O)CO)[C@@]4(C)CC[C@]3([H])[C@@]1(C)CC[C@@H](O)C2

InChI

1S/C21H34O3/c1-20-9-7-14(23)11-13(20)3-4-15-16-5-6-18(19(24)12-22)21(16,2)10-8-17(15)20/h13-18,22-23H,3-12H2,1-2H3/t13-,14+,15-,16-,17-,18+,20-,21-/m0/s1

InChI key

CYKYBWRSLLXBOW-GDYGHMJCSA-N

Gene Information

human ... GABRA1(2554) , GABRA2(2555) , GABRA3(2556) , GABRA4(2557) , GABRA5(2558) , GABRA6(2559) , GABRB1(2560) , GABRB2(2561) , GABRB3(2562)
rat ... Gabra2(29706)

General description

3α21-Dihydroxy-5α-pregnan-20-one (THDOC) is a neurosteroid. It is synthesized in a two-step process from deoxycorticosterone (DOC) via 5α-dihydrodeoxycorticosterone (DHDOC) intermediate with enzymes 5α-reductase and 3α-hydroxysteroid oxidoreductase catalyzing these steps respectively.

Application

3α,21-Dihydroxy-5α-pregnan-20-one (THDOC) has been used:
  • as an γ-aminobutyric acid type A receptor (γ-GABAA) agonist in voltage-clamp measurements studies in Xenopus oocytes
  • to test its effect on the spike-wave discharges (SWD) finasteride-treated rats
  • in electrophysiological studies with dentate granule cells (DGCs) post controlled cortical impact (CCI) -induced brain injury

Biochem/physiol Actions

3α,21-Dihydroxy-5α-pregnan-20-one (THDOC) is a positive allosteric modulator of the γ-aminobutyric acid A receptor (GABAA). By modulating GABAA receptor, THDOC allows sustained hyperpolarization and an increase in chloride influx and membrane conductance in neurons. THDOC, thus modulates neuronal excitability. It possesses anxiolytic, anticonvulsant and sedative properties. The levels of THDOC show variation in different physiological states. A low THDOC level in the mensural phase is speculated to play a role in the pathogenesis of catamenial epilepsy (CE) in women. However, elevated levels are reported in depression. THDOC may have an indirect role in the hypothalamic-pituitary–adrenal (HPA) axis activation during acute stress.

Features and Benefits

This compound is a featured product for Neuroscience research. Click here to discover more featured Neuroscience products. Learn more about bioactive small molecules for other areas of research at sigma.com/discover-bsm.

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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D Eser et al.
Neuroscience, 138(3), 1041-1048 (2005-11-29)
Certain neuroactive steroids modulate ligand-gated ion channels via non-genomic mechanisms. Especially 3alpha-reduced pregnane steroids are potent positive allosteric modulators of the GABA type A-receptor. During major depression there is a dysequilibrium of 3alpha-reduced neuroactive steroids, which is corrected by clinically
Patrizia Porcu et al.
Alcoholism, clinical and experimental research, 34(3), 432-442 (2009-12-24)
Acute ethanol administration increases plasma and brain levels of progesterone and deoxycorticosterone-derived neuroactive steroids (3alpha,5alpha)-3-hydroxypregnan-20-one (3alpha,5alpha-THP) and (3alpha,5alpha)-3,21-dihydroxypregnan-20-one (3alpha,5alpha-THDOC) in rats. However, little is known about ethanol effects on GABAergic neuroactive steroids in mice, nonhuman primates, or humans. We investigated
Kuldeep H Kaur et al.
The Journal of biological chemistry, 284(12), 7889-7896 (2009-01-15)
GABA(A) receptors mediate inhibitory neurotransmission in the mammalian brain via synaptic and extrasynaptic receptors. The delta (delta)-subunit-containing receptors are expressed exclusively extra-synaptically and mediate tonic inhibition. In the present study, we were interested in determining the architecture of receptors containing
Jhimly Sarkar et al.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 31(50), 18198-18210 (2011-12-16)
The hypothalamic-pituitary-adrenal (HPA) axis, which mediates the body's response to stress, is largely under GABAergic control. Here we demonstrate that corticotropin-releasing hormone (CRH) neurons are modulated by the stress-derived neurosteroid, tetrahydrodeoxycorticosterone (THDOC), acting on δ subunit-containing GABA(A) receptors (GABA(A)Rs). Under
Junn-Liang Chang et al.
American journal of physiology. Renal physiology, 299(1), F43-F48 (2010-04-02)
Recently, we demonstrated a chronic neurosteroid-dependent inhibition of activity-dependent spinal reflex potentiation (SRP), but it remains unclear whether neurosteroids acutely modulate SRP induction. This study shows progesterone as well as two of its 3alpha,5alpha-derivatives, allopregnalonone and 3alpha,5alpha-tetrahydrodeoxycorticosterone (THDOC), to be
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