|Synonyms||NSC-97078; U-0949; UC-1010; NSC97078; U0949; UC1010; NSC 97078; U 0949; UC 1010; Isopregnanolone; Allopregnanolon; Sepranolone; 516-55-2; 5alpha-Pregnan-3beta-ol-20-one|
|Storage and Handling||Dry, dark and at 0 – 4 C for short term (days to weeks) or -20 C for long term (months to years).|
Allopregnanolone, also known as Sepranolone and Isopregnanolone, is a GABA receptor modulating steroid antagonist and 11-betahydroxysteroid dehydrogenase type 1 (11β-HSD1). Sepranolone is a powerful neurological compound, produced naturally in the body, that modulates the effects of Allopregnanolone (ALLO). ALLO is a potent neurosteroid implicated in stress- and compulsion-related conditions ranging from Tourette to OCD, PTSD, compulsive gambling, addiction, PMDD, Menstrual Migraine.
Allopregnanolone Mechanism of Action
Allopregnanolone is an endogenous inhibitory pregnane neurosteroid. It is made from progesterone, and is a positive allosteric modulator of the action of γ-aminobutyric acid (GABA) at GABAA receptor. Allopregnanolone has effects similar to those of other positive allosteric modulators of the GABA action at GABAA receptor such as the benzodiazepines, including anxiolytic, sedative, and anticonvulsant activity. Endogenously produced allopregnanolone exerts a neurophysiological role by fine-tuning of GABAA receptor and modulating the action of several positive allosteric modulators and agonists at GABAA receptor.
Allopregnanolone acts as a highly potent positive allosteric modulator of the GABAA receptor. While allopregnanolone, like other inhibitory neurosteroids such as THDOC, positively modulates all GABAA receptor isoforms, those isoforms containing δ subunits exhibit the greatest potentiation. Allopregnanolone has also been found to act as a positive allosteric modulator of the GABAA-ρ receptor, though the implications of this action are unclear. In addition to its actions on GABA receptors, allopregnanolone, like progesterone, is known to be a negative allosteric modulator of nACh receptors, and also appears to act as a negative allosteric modulator of the 5-HT3 receptor. Along with the other inhibitory neurosteroids, allopregnanolone appears to have little or no action at other ligand-gated ion channels, including the NMDA, AMPA, kainate, and glycine receptors.
The mechanism by which neurosteroid GABAA receptor PAMs like brexanolone have antidepressant effects is unknown. Other GABAA receptor PAMs, such as benzodiazepines, are not thought of as antidepressants and have no proven efficacy, despite clinicians prescribing Alprazolam for depression in the past. Neurosteroid GABAA receptor PAMs are known to interact with GABAA receptors and sub-populations differently than benzodiazepines. As examples, GABAA receptor-potentiating neurosteroids may preferentially target δ subunit-containing GABAA receptors, and enhance both tonic and phasic inhibition mediated by GABAA receptors. It is also possible that neurosteroids like allopregnanolone may act on other targets, including membrane progesterone receptors, T-type voltage-gated calcium channels, and others, to mediate antidepressant effects.
Allopregnanolone is a naturally produced steroid that acts on the brain. As a medication, it is sold under the brand name Zulresso and used to treat postpartum depression. It is used by injection into a vein over a 60-hour period under medical supervision.
Side effects of Allopregnanolone may include sedation, sleepiness, dry mouth, hot flashes, and loss of consciousness. It is a neurosteroid and acts as a positive allosteric modulator of the GABAA receptor, the major biological target of the inhibitory neurotransmitter γ-aminobutyric acid (GABA).
Allopregnanolone was approved for medical use in the United States in 2019. The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication. The long administration time, as well as the cost for a one-time treatment, have raised concerns about accessibility for many women.