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Epipregnanolone
Epipregnanolone, also known as 3β-hydroxy-5β-pregnan-20-one, 3β,5β-tetrahydroprogesterone, or 3β,5β-THP, is an endogenous neurosteroid. It acts as a negative allosteric modulator of the GABAA receptor and reverses the effects of potentiators like allopregnanolone. Epipregnanolone is biosynthesized from progesterone by the actions of 5β-reductase and 3β-hydroxysteroid dehydrogenase, with 5β-dihydroprogesterone as the intermediate in this two-step transformation. Epipregnanolone is not a progestogen itself, but via metabolization into other steroids, behaves indirectly as one. The sulfate of epipreganolone, epipregnanolone sulfate, is a negative allosteric modulator of the NMDA and GABAA receptors and also acts as a TRPM3 channel activator. Chemistry See also * Isopregnanolone * 3β-Dihydroprogesterone * Pregnanolone * 5α-Dihydroprogesterone * 3β-Androstanediol 3β-Androstanediol, also known as 5α-androstane-3β,17β-diol, and sometimes shortened in the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3β-Dihydroprogesterone
3β-Dihydroprogesterone (3β-DHP), also known as 3β-hydroxyprogesterone, or pregn-4-en-3β-ol-20-one (4-pregnenolone, δ4-pregnenolone), is an endogenous steroid. It is biosynthesized by 3β-hydroxysteroid dehydrogenase from progesterone. Unlike 3α-dihydroprogesterone (3α-DHP), 3β-DHP does not act as a positive allosteric modulator of the GABAA receptor, which is in accordance with the fact that other 3β-hydroxylated progesterone metabolites such as isopregnanolone and epipregnanolone similarly do not act as potentiators of this receptor and instead inhibit it as well as reverse the effects of potentiators like allopregnanolone. 3β-DHP has been reported to possess about the same potency as progesterone in a bioassay of progestogenic activity, whereas 3α-DHP was not assessed. See also * 5α-Dihydroprogesterone * 5β-Dihydroprogesterone * 3β-Androstanediol * Pregnenolone * Progesterone 3-acetyl enol ether * Quingestrone Quingestrone, also known as progesterone 3-cyc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurosteroids
Neurosteroids, also known as neuroactive steroids, are endogenous or exogenous steroids that rapidly alter neuronal excitability through interaction with ligand-gated ion channels and other cell surface receptors. The term ''neurosteroid'' was coined by the French physiologist Étienne-Émile Baulieu and refers to steroids synthesized in the brain. The term, ''neuroactive steroid'' refers to steroids that can be synthesized in the brain, or are synthesized by an endocrine gland, that then reach the brain through the bloodstream and have effects on brain function. The term neuroactive steroids was first coined in 1992 by Steven Paul and Robert Purdy. In addition to their actions on neuronal membrane receptors, some of these steroids may also exert effects on gene expression via nuclear steroid hormone receptors. Neurosteroids have a wide range of potential clinical applications from sedation to treatment of epilepsy and traumatic brain injury. Ganaxolone, a synthetic analog of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epipregnanolone Sulfate
Epipregnanolone, also known as 3β-hydroxy-5β-pregnan-20-one, 3β,5β-tetrahydroprogesterone, or 3β,5β-THP, is an endogenous neurosteroid. It acts as a negative allosteric modulator of the GABAA receptor and reverses the effects of potentiators like allopregnanolone. Epipregnanolone is biosynthesized from progesterone by the actions of 5β-reductase and 3β-hydroxysteroid dehydrogenase, with 5β-dihydroprogesterone as the intermediate in this two-step transformation. Epipregnanolone is not a progestogen itself, but via metabolization into other steroids, behaves indirectly as one. The sulfate of epipreganolone, epipregnanolone sulfate, is a negative allosteric modulator of the NMDA and GABAA receptors and also acts as a TRPM3 channel activator. Chemistry See also * Isopregnanolone * 3β-Dihydroprogesterone * Pregnanolone * 5α-Dihydroprogesterone * 3β-Androstanediol 3β-Androstanediol, also known as 5α-androstane-3β,17β-diol, and sometimes shortened in the lit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allopregnanolone
Allopregnanolone is a naturally occurring neurosteroid which is made in the body from the hormone progesterone. As a medication, allopregnanolone is referred to as brexanolone, 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 brexanolone 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). Brexanolone 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. Medical uses Brexanolone is used to treat postpartum d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progesterone
Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the major progestogen in the body. Progesterone has a variety of important functions in the body. It is also a crucial metabolic intermediate in the production of other endogenous steroids, including the sex hormones and the corticosteroids, and plays an important role in brain function as a neurosteroid. In addition to its role as a natural hormone, progesterone is also used as a medication, such as in combination with estrogen for contraception, to reduce the risk of uterine or cervical cancer, in hormone replacement therapy, and in feminizing hormone therapy. It was first prescribed in 1934. Biological activity Progesterone is the most important progestogen in the body. As a potent agonist of the nuclear progesterone receptor (nP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pregnanolone
Pregnanolone, also known as eltanolone, is an endogenous inhibitory neurosteroid which is produced in the body from progesterone. It is closely related to allopregnanolone, which has similar properties. Biological activity Pregnanolone is a positive allosteric modulator of the GABAA receptor, as well as a negative allosteric modulator of the glycine receptor. Biological function Pregnanolone has sedative, anxiolytic, anesthetic, and anticonvulsant effects. During pregnancy, pregnanolone and allopregnanolone are involved in sedation and anesthesia of the fetus. Biochemistry Pregnanolone is synthesized from progesterone via the enzymes 5β-reductase and 3α-hydroxysteroid dehydrogenase, with 5β-dihydroprogesterone occurring as a metabolic intermediate. The elimination half-life of pregnanolone is between 0.9 and 3.5 hours. Chemistry Pregnanolone, also known as 3α,5β-tetrahydroprogesterone (3α,5β-THP) or as 5β-pregnan-3α-ol-20-one, is a naturally occurring pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurosteroid
Neurosteroids, also known as neuroactive steroids, are endogenous or exogenous steroids that rapidly alter neuronal excitability through interaction with ligand-gated ion channels and other cell surface receptors. The term ''neurosteroid'' was coined by the French physiologist Étienne-Émile Baulieu and refers to steroids synthesized in the brain. The term, ''neuroactive steroid'' refers to steroids that can be synthesized in the brain, or are synthesized by an endocrine gland, that then reach the brain through the bloodstream and have effects on brain function. The term neuroactive steroids was first coined in 1992 by Steven Paul and Robert Purdy. In addition to their actions on neuronal membrane receptors, some of these steroids may also exert effects on gene expression via nuclear steroid hormone receptors. Neurosteroids have a wide range of potential clinical applications from sedation to treatment of epilepsy and traumatic brain injury. Ganaxolone, a synthetic analog of the end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAA Receptor Negative Allosteric Modulators
The GABAA receptor (GABAAR) is an ionotropic receptor and ligand-gated ion channel. Its endogenous ligand is γ-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the central nervous system. Upon opening, the GABAA receptor on the postsynaptic cell is selectively permeable to chloride ions (Cl−) and, to a lesser extent, bicarbonate ions (HCO3−). Depending on the membrane potential and the ionic concentration difference, this can result in ionic fluxes across the pore. If the membrane potential is higher than the equilibrium potential (also known as the reversal potential) for chloride ions, when the receptor is activated Cl− will flow into the cell. This causes an inhibitory effect on neurotransmission by diminishing the chance of a successful action potential occurring at the postsynaptic cell. The reversal potential of the GABAA-mediated inhibitory postsynaptic potential (IPSP) in normal solution is −70 mV, contrasting the GABAB IPSP (-100 mV). The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3β-Androstanediol
3β-Androstanediol, also known as 5α-androstane-3β,17β-diol, and sometimes shortened in the literature to 3β-diol, is an endogenous steroid hormone and a metabolite of androgens like dehydroepiandrosterone (DHEA) and dihydrotestosterone (DHT). Biological activity 3β-Androstanediol is a selective, high- affinity agonist of the ERβ, and hence, an estrogen. In contrast to ERβ, 3β-androstanediol does not bind to the androgen receptor (AR). 3β-Androstanediol has been reported to also bind to ERα with low nanomolar affinity, with several-fold lower affinity relative to ERβ. It has approximately 3% and 7% of the affinity of estradiol at the ERα and ERβ, respectively. Unlike 3α-androstanediol, 3β-androstanediol does not bind to the GABAA receptor. 3β-Androstanediol may be the primary endogenous ligand of ERβ in the prostate gland, and as a result of activation of the ERβ, 3β-androstanediol has antiproliferative effects against prostate cancer cells. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5α-Dihydroprogesterone
5α-Dihydroprogesterone (5α-DHP, allopregnanedione, or 5α-pregnane-3,20-dione) is an endogenous progestogen and neurosteroid that is synthesized from progesterone. It is also an intermediate in the synthesis of allopregnanolone and isopregnanolone from progesterone. 5α-DHP is metabolized by the aldo-keto reductases (AKRs) AKR1C1, AKR1C2, and AKR1C4 with high catalytic efficiency. AKR1C1 preferentially forms 20α-hydroxy-5α-pregnane-3-one while AKR1C2 preferentially forms allopregnanolone. Similarly AKR1C1 reduces and consequently inactivates allopregnanolone into 5α-pregnane-3α,20α-diol. In contrast to the other AKRs, AKR1C3 has low catalytic efficiency for reduction of 5α-DHP. These AKRs are highly expressed in the human liver and mammary gland but have relatively modest expression in the human brain and uterus. 5α-DHP is an agonist of the progesterone receptor and a positive allosteric modulator of the GABAA receptor (albeit with an affinity for this receptor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isopregnanolone
Isopregnanolone, also known as isoallopregnanolone and epiallopregnanolone, as well as sepranolone (), and as 3β-hydroxy-5α-pregnan-20-one or 3β,5α-tetrahydroprogesterone (3β,5α-THP), is an endogenous neurosteroid and a natural 3β-epimer of allopregnanolone.Öfverman, C., Strömberg, J., Birzniece, V., Turkmen, S., Hill, M., Lundgren, P., ... & Johansson, I. M. (2009). The progesterone metabolite isoallopregnanolone is a subunit-selective antagonist of the GABA-A receptor. Chicago It has been reported to act as a subunit-selective negative allosteric modulator of the GABAA receptor, and antagonizes in animals and humans some but not all of the GABAA receptor-mediated effects of allopregnanolone, such as anesthesia, sedation, and reduced saccadic eye movements, but not learning impairment. Isopregnanolone has no hormonal effects and appears to have no effect on the GABAA receptor by itself; it selectively antagonizes allopregnanolone and does not affect the effects of ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
