Pregnanolone, 3α-Hydroxy-5β-pregnan-20-one, 3α-Hydroxy-5β-tetrahydroprogesterone
Empirical Formula (Hill Notation):
CAS Number:
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PubChem Substance ID:
Pricing and availability is not currently available.

biological source

synthetic (organic)

Quality Level


≥98% (TLC)




chloroform: 50 mg/mL, clear, colorless

shipped in


storage temp.

room temp

SMILES string




InChI key


Gene Information

rat ... Gabra2(29706)


25 mg in glass insert

Biochem/physiol Actions

5β-Pregnan-3α-ol-20-one or pregnanolone is a neurosteroid that acts as a positive allosteric modulator (PAMs) of γ-aminobutyric acid A receptors (GABAARs). It mediates anti-convulsive, anxiolytic and sedative effects. Pregnanolone inhibits γ-aminobutyric acid C receptor (GABAC) receptor-based response and favors GABAA receptor-mediated currents.


Health hazard

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Precautionary Statements

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


NONH for all modes of transport

WGK Germany


Certificate of Analysis
Certificate of Origin
Selwyn S Jayakar et al.
The Journal of biological chemistry, 295(33), 11495-11512 (2020-06-17)
Allopregnanolone (3α5α-P), pregnanolone, and their synthetic derivatives are potent positive allosteric modulators (PAMs) of GABAA receptors (GABAARs) with in vivo anesthetic, anxiolytic, and anti-convulsant effects. Mutational analysis, photoaffinity labeling, and structural studies have provided evidence for intersubunit and intrasubunit steroid-binding...
P Li et al.
British journal of pharmacology, 171(23), 5446-5457 (2014-08-15)
Neurosteroids potentiate responses of the GABAA receptor to the endogenous agonist GABA. Here, we examined the ability of neurosteroids to potentiate responses to the allosteric activators etomidate, pentobarbital and propofol. Electrophysiological assays were conducted on rat α1β2γ2L GABAA receptors expressed...
Samuel O Adeosun et al.
PloS one, 7(11), e50040-e50040 (2012-12-05)
Restorative/protective therapies to restore dopamine neurons in the substantia nigra pars compacta (SNpc) are greatly needed to effectively change the debilitating course of Parkinson's disease. In this study, we tested the therapeutic potential of a neurogenic neurosteroid, allopregnanolone, in the...
Jane Evans et al.
Neuropharmacology, 63(8), 1315-1326 (2012-09-04)
Chronic stress has been implicated as a causal factor in depression and anxiety, and is associated with neuroendocrine dysfunction and impaired hippocampal neurogenesis. The neurosteroid allopregnanolone (3α,5α-THP; ALLO) has been shown to be reduced in depressed patients. ALLO is "stress...
Sara K Bengtsson et al.
Current Alzheimer research, 10(1), 38-47 (2012-11-20)
Previously, we have shown that chronic treatment with allopregnanolone (ALLO) for three months impaired learning function in the Swe/PS1 mouse model. ALLO is a neurosteroid, produced in the CNS and a GABAA receptor agonist. ALLO modulates the general inhibitory system...

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