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Etiocholanolone
Etiocholanolone, also known as 5β-androsterone, as well as 3α-hydroxy-5β-androstan-17-one or etiocholan-3α-ol-17-one, is an etiocholane (5β-androstane) steroid as well as an endogenous 17-ketosteroid that is produced from the metabolism of testosterone. It causes fever, immunostimulation, and leukocytosis, and is used to evaluate adrenal cortex function, bone marrow performance, and in neoplastic disease to stimulate the immune system. Etiocholanolone is also known to be an inhibitory androstane neurosteroid, acting as a positive allosteric modulator of the GABAA receptor, and possesses anticonvulsant effects. The unnatural enantiomer of etiocholanolone is more potent as a positive allosteric modulator of GABAA receptors and as an anticonvulsant than the natural form. Etiocholanolone has been studied as a pyrogenic steroid in the so-called steroid fever (or etiocholanolone fever), a condiditon similar to familial mediterranean fever (FMF). Etiocholanolone (like pregnano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
17-ketosteroid
150px, Androstenedione 150px, Androsterone 150px, Estrone A ketosteroid, or an oxosteroid, is a steroid in which a hydrogen atom has been replaced with a ketone (C=O) group. A 17-ketosteroid is a ketosteroid in which the ketone is located specifically at the C17 position (in the upper right corner of most structure diagrams). Examples of 17-ketosteroids include: * Androstenedione * Androstanedione * Androsterone * Dehydroepiandrosterone * Epiandrosterone * Epietiocholanolone * Etiocholanolone 17-Ketosteroids are endogenous steroid hormones. See also * Hydroxysteroid * Hydroxysteroid dehydrogenase Hydroxysteroid dehydrogenases (HSDs) are a group of alcohol oxidoreductases that catalyze the dehydrogenation of hydroxysteroids. These enzymes also catalyze the reverse reaction, acting as ketosteroid reductases (KSRs). There are four types, cl ... External links * * Ketones Steroids {{steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etiocholane
Etiocholane, also known as 5β-androstane or 5-epiandrostane, is an androstane (C19) steroid. It is the 5β-isomer of androstane. Etiocholanes include 5β-androstanedione, 5β-dihydrotestosterone, 3α,5β-androstanediol, 3β,5β-androstanediol, etiocholanolone, epietiocholanolone, and 3α,5β-androstanol. 17β-Ethyletiocholanes, or 5β-pregnanes, include 5β-dihydroprogesterone, pregnanolone, and epipregnanolone, as well as pregnanediol Pregnanediol, or 5β-pregnane-3α,20α-diol, is an inactive metabolic product of progesterone. A test can be done to measure the amount of pregnanediol in urine, which offers an indirect way to measure progesterone levels in the body. From the ur ... and pregnanetriol. See also * C19H32 References {{DEFAULTSORT:Androstane, 5β- Etiocholanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAA Receptor
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). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androsterone
Androsterone, or 3α-hydroxy-5α-androstan-17-one, is an endogenous steroid hormone, neurosteroid, and putative pheromone. It is a weak androgen with a potency that is approximately 1/7 that of testosterone. Androsterone is a metabolite of testosterone and dihydrotestosterone (DHT). In addition, it can be converted back into DHT via 3α-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase, bypassing conventional intermediates such as androstanedione and testosterone, and as such, can be considered to be a metabolic intermediate in its own right. Androsterone is also known to be an inhibitory androstane neurosteroid, acting as a positive allosteric modulator of the GABAA receptor, and possesses anticonvulsant effects. The unnatural enantiomer of androsterone is more potent as a positive allosteric modulator of GABAA receptors and as an anticonvulsant than the natural form. Androsterone's 3β-isomer is epiandrosterone, and its 5β-epimer is etiocholanolone. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Intermediate
Metabolic intermediates are molecules that are the precursors or metabolites of biologically significant molecules. Although these intermediates are of relatively minor direct importance to cellular function, they can play important roles in the allosteric regulation of enzymes. Clinical significance Some can be useful in measuring rates of metabolic processes (for example, 3,4-dihydroxyphenylacetic acid or 3-aminoisobutyrate). Because they can represent unnatural points of entry into natural metabolic pathways, some (such as AICA ribonucleotide) are of interest to researchers in developing new therapies. See also * Metabolism Metabolism {{chem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5β-dihydrotestosterone
5β-Dihydrotestosterone (5β-DHT), also known as 5β-androstan-17β-ol-3-one or as etiocholan-17β-ol-3-one, is an etiocholane (5β-androstane) steroid as well as an inactive metabolite of testosterone formed by 5β-reductase in the liver and bone marrow and an intermediate in the formation of 3α,5β-androstanediol and 3β,5β-androstanediol (by 3α- and 3β-hydroxysteroid dehydrogenase) and, from them, respectively, etiocholanolone and epietiocholanolone (by 17β-hydroxysteroid dehydrogenase). Unlike its isomer 5α-dihydrotestosterone (5α-DHT or simply DHT), 5β-DHT either does not bind to or binds only very weakly to the androgen receptor. 5β-DHT is notable among metabolites of testosterone in that, due to the fusion of the A and B rings in the ''cis'' orientation, it has an extremely angular molecular shape, and this could be related to its lack of androgenic activity. 5β-DHT, unlike 5α-DHT, is also inactive in terms of neurosteroid activity, although its metabolite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Menstrual Cycle
The menstrual cycle is a series of natural changes in hormone production and the structures of the uterus and ovaries of the female reproductive system that make pregnancy possible. The ovarian cycle controls the production and release of eggs and the cyclic release of estrogen and progesterone. The uterine cycle governs the preparation and maintenance of the lining of the uterus (womb) to receive an embryo. These cycles are concurrent and coordinated, normally last between 21 and 35 days, with a median length of 28 days, and continue for about 30–45 years. Naturally occurring hormones drive the cycles; the cyclical rise and fall of the follicle stimulating hormone prompts the production and growth of oocytes (immature egg cells). The hormone estrogen stimulates the uterus lining ( endometrium) to thicken to accommodate an embryo should fertilization occur. The blood supply of the thickened lining provides nutrients to a successfully implanted embryo. If implantation does n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stress (biology)
Stress, either physiological, biological or psychological, is an organism's response to a stressor such as an environmental condition. Stress is the body's method of reacting to a condition such as a threat, challenge or physical and psychological barrier. There are two hormones that an individual produces during a stressful situation, these are well known as adrenaline and cortisol. There are two kinds of stress hormone levels. Resting (basal) cortisol levels are normal everyday quantities that are essential for standard functioning. Reactive cortisol levels are increases in cortisol in response to stressors. Stimuli that alter an organism's environment are responded to by multiple systems in the body. In humans and most mammals, the autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis are the two major systems that respond to stress. The sympathoadrenal medullary (SAM) axis may activate the fight-or-flight response through the sympathetic nervous system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid
A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and as signaling molecules. Hundreds of steroids are found in plants, animals and fungi. All steroids are manufactured in cells from the sterols lanosterol (opisthokonts) or cycloartenol (plants). Lanosterol and cycloartenol are derived from the cyclization of the triterpene squalene. The steroid core structure is typically composed of seventeen carbon atoms, bonded in four " fused" rings: three six-member cyclohexane rings (rings A, B and C in the first illustration) and one five-member cyclopentane ring (the D ring). Steroids vary by the functional groups attached to this four-ring core and by the oxidation state of the rings. Sterols are forms of steroids with a hydroxy group at position three and a skeleton derived from cholestane. ''A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflammasome
Inflammasomes are cytosolic multiprotein oligomers of the innate immune system responsible for the activation of inflammatory responses. Activation and assembly of the inflammasome promotes proteolytic cleavage, maturation and secretion of pro-inflammatory cytokines interleukin 1β (IL-1β) and interleukin 18 (IL-18), as well as cleavage of Gasdermin-D. The N-terminal fragment resulting from this cleavage induces a pro-inflammatory form of programmed cell death distinct from apoptosis, referred to as pyroptosis, and is responsible for secretion of the mature cytokines, presumably through the formation of pores in the plasma membrane. Inflammasome activation is initiated by different kinds of cytosolic pattern recognition receptors (PRRs) that respond to either microbe-derived pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs) generated by the host cell. Pattern recognition receptors involved in inflammasomes comprise NLRs (nucleoti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrin
''MEFV'' (Mediterranean fever) is a human gene that provides instructions for making a protein called pyrin (also known as marenostrin). Pyrin is produced in certain white blood cells (neutrophils, eosinophils and monocytes) that play a role in inflammation and in fighting infection. Inside these white blood cells, pyrin is found with the cytoskeleton, the structural framework that helps to define the shape, size, and movement of a cell. Pyrin's protein structure also allows it to interact with other molecules involved in fighting infection and in the inflammatory response. Although pyrin's function is not fully understood, it likely assists in keeping the inflammation process under control. Research indicates that pyrin helps regulate inflammation by interacting with the cytoskeleton. Pyrin may direct the migration of white blood cells to sites of inflammation and stop or slow the inflammatory response when it is no longer needed. The ''MEFV'' gene is located on the short (p) arm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
