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11-Ketoprogesterone
11-Ketoprogesterone (brand name Ketogestin; former developmental code names Bio 66, U-1258), or 11-oxoprogesterone, also known as pregn-4-ene-3,11,20-trione, is a pregnane steroid related to cortisone (11-keto-17α,21-dihydroxyprogesterone) that was formerly used in veterinary medicine in the treatment of bovine ketosis. It was synthesized in 1940. The steroid has profound effects on carbohydrate metabolism and possesses activities associated with adrenal cortex hormones like cortisone. However, it is non-toxic even in high dosages, suggesting that it lacks conventional glucocorticoid activity, and it does not possess mineralocorticoid activity, unlike other adrenocortical hormones. 11-Ketoprogesterone may act through membrane glucocorticoid receptors. 11-Ketoprogesterone is reportedly devoid of androgenic, estrogenic, and progestogenic activity. 11β-Hydroxyprogesterone has also been reported to be devoid of progestogenic activity, but has subsequently been reported to possess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
21-Deoxycortisone
21-Deoxycortisone, also known as 21-desoxycortisone, 11-keto-17α-hydroxyprogesterone, or 17α-hydroxypregn-4-ene-3,11,20-trione, is a naturally occurring, endogenous steroid and minor intermediate and metabolite in corticosteroid metabolism. It is related to 21-deoxycortisol (11β,17α-dihydroxyprogesterone) and is reversibly formed from it by 11β-hydroxysteroid dehydrogenase, analogously to the reversible formation of cortisone from cortisol. 21-Deoxycortisone can be transformed into cortisone by 21-hydroxylase. See also * 11-Dehydrocorticosterone * 11-Ketoprogesterone * 17α-Hydroxyprogesterone 17α-Hydroxyprogesterone (17α-OHP), also known as 17-OH progesterone (17-OHP), or hydroxyprogesterone (OHP), is an endogenous progestogen steroid hormone related to progesterone. It is also a chemical intermediate in the biosynthesis of many ot ... References Corticosteroids Human metabolites Pregnanes Triketones {{steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
11-Dehydrocorticosterone
11-Dehydrocorticosterone (11-DHC), also known as 11-oxocorticosterone or 17-deoxycortisone, as well as 21-hydroxypregn-4-ene-3,11,20-trione, is a naturally occurring, endogenous corticosteroid related to cortisone and corticosterone. It is a potent mineralocorticoid, with generally greater such activity than that of corticosterone. See also * 21-Deoxycortisone * 11-Ketoprogesterone * 11-Deoxycorticosterone 11-Deoxycorticosterone (DOC), or simply deoxycorticosterone, also known as 21-hydroxyprogesterone, as well as desoxycortone (INN), deoxycortone, and cortexone, is a steroid hormone produced by the adrenal gland that possesses mineralocorticoid ac ... References Primary alcohols Enones Mineralocorticoids Pregnanes Triketones {{steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pregnane
Pregnane, also known as 17β-ethylandrostane or as 10β,13β-dimethyl-17β-ethylgonane, is a C21 steroid and, indirectly, a parent of progesterone. It is a parent hydrocarbon for two series of steroids stemming from 5α-pregnane (originally allopregnane) and 5β-pregnane (17β-ethyletiocholane). It has a gonane core. 5β-Pregnane is the parent of pregnanediones, pregnanolones, and pregnanediols, and is found largely in urine as a metabolic product of 5β-pregnane compounds. Pregnanes Pregnanes are steroid derivatives with carbons present at positions 1 through 21. Most biologically significant pregnane derivatives fall into one of two groups: pregnenes and pregnadienes. Another class is pregnatrienes. Pregnenes Pregnenes have a double bond. Examples include: * Cortisone * Hydrocortisone * Progesterone Pregnadienes Pregnadienes have two double bonds. Examples include: * Cyproterone acetate * Danazol * Fluocinonide See also * 5β-Pregnane * Pregnanedione * Pregna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progestogen
Progestogens, also sometimes written progestagens or gestagens, are a class of natural or synthetic steroid hormones that bind to and activate the progesterone receptors (PR). Progesterone is the major and most important progestogen in the body. The progestogens are named for their function in maintaining pregnancy (i.e., ''progestational''), although they are also present at other phases of the estrous and menstrual cycles. The progestogens are one of three types of sex hormones, the others being estrogens like estradiol and androgens/anabolic steroids like testosterone. In addition, they are one of the five major classes of steroid hormones, the others being the androgens, estrogens, glucocorticoids, and mineralocorticoids, as well as the neurosteroids. All endogenous progestogens are characterized by their basic 21-carbon skeleton, called a pregnane skeleton (C21). In similar manner, the estrogens possess an estrane skeleton (C18), and androgens, an androstane skeleton (C19). ... [...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] |
Negative Allosteric Modulator
In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a receptor to change that receptor's response to stimulus. Some of them, like benzodiazepines, are drugs. The site that an allosteric modulator binds to (i.e., an ''allosteric site'') is not the same one to which an endogenous agonist of the receptor would bind (i.e., an ''orthosteric site''). Modulators and agonists can both be called receptor ligands. Allosteric modulators can be 1 of 3 types either: positive, negative or neutral. Positive types increase the response of the receptor by increasing the probability that an agonist will bind to a receptor (i.e. affinity), increasing its ability to activate the receptor (i.e. efficacy), or both. Negative types decrease the agonist affinity and/or efficacy. Neutral types don't affect agonist activity but can stop other modulators from binding to an allosteric site. Some modulators also work as allosteric agonists. The term "allosteric" d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Inhibitor
An enzyme inhibitor is a molecule that binds to an enzyme and blocks its activity. Enzymes are proteins that speed up chemical reactions necessary for life, in which substrate molecules are converted into products. An enzyme facilitates a specific chemical reaction by binding the substrate to its active site, a specialized area on the enzyme that accelerates the most difficult step of the reaction. An enzyme inhibitor stops ("inhibits") this process, either by binding to the enzyme's active site (thus preventing the substrate itself from binding) or by binding to another site on the enzyme such that the enzyme's catalysis of the reaction is blocked. Enzyme inhibitors may bind reversibly or irreversibly. Irreversible inhibitors form a chemical bond with the enzyme such that the enzyme is inhibited until the chemical bond is broken. By contrast, reversible inhibitors bind non-covalently and may spontaneously leave the enzyme, allowing the enzyme to resume its function. Reve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
11β-hydroxyprogesterone
11β-Hydroxyprogesterone (11β-OHP), also known as 21-deoxycorticosterone, as well as 11β-hydroxypregn-4-ene-3,20-dione, is a naturally occurring, endogenous steroid and derivative of progesterone. It is a potent mineralocorticoid. Syntheses of 11β-OHP from progesterone is catalyzed by the steroid 11β-hydroxylase (CYP11B1) enzyme, and, to a lesser extent, by the aldosterone synthase enzyme (CYP11B2). Function Along with its epimer 11α-hydroxyprogesterone (11α-OHP), 11β-OHP has been identified as a very potent competitive inhibitor of both isoforms ( 1 and 2) of 11β-hydroxysteroid dehydrogenase (11β-HSD). Outcome of 21-hydroxylase deficiency It has been known since 1987 that increased levels of 11β-OHP occur in 21-hydroxylase deficiency. A study in 2017 has shown that in subjects with 21-hydroxylase deficiency, serum 11β-OHP concentrations range from 0.012 to 3.37 ng/mL, while in control group it was below detection limit of 0.012 ng/mL. 21-hydroxylase is an enzyme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
11α-hydroxyprogesterone
11α-Hydroxyprogesterone (11α-OHP), or 11α-hydroxypregn-4-ene-3,20-dione is an endogenous steroid and metabolite of progesterone. It is a weak antiandrogen, and is devoid of androgenic, estrogenic, and progestogenic activity. 11α-OHP was investigated as a topical antiandrogen for the treatment of androgen-dependent skin conditions in the early 1950s, and was found to produce some benefit. In 1995, 11α-OHP, along with its epimer 11β-hydroxyprogesterone, was identified as a very potent competitive inhibitor of both isoforms ( 1 and 2) of 11β-hydroxysteroid dehydrogenase (11β-HSD). It is notably not metabolized by 11β-HSD2. 11α-OHP is a more potent inhibitor of 11β-HSD than enoxolone (glycyrrhetinic acid) or carbenoxolone ''in vitro'' ( IC50 = 0.9 nM; IC50 = 5 nM in transfected cells). The compound has been found to be highly active in conferring mineralocorticoid sodium-retaining activity of corticosterone ''in vivo'' in rat bioassays and in increasing blood pressur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
9α-bromo-11-ketoprogesterone
Bromoketoprogesterone (BKP), also known as 9α-bromo-11-oxoprogesterone (BOP), and known by the tentative brand name Braxarone ( Squibb), is an orally active progestin which does not appear to have been marketed. Pharmacology Pharmacodynamics Whereas 11-ketoprogesterone and 11β-hydroxyprogesterone are virtually devoid of progestogenic activity (although 11β-hydroxyprogesterone has been reported to possess about 1% of the progestogenic activity of progesterone), the progestogenic activity of BKP is restored and is in fact relatively high. In contrast, 9α-fluoro-11β-hydroxyprogesterone has much lower progestogenic activity with only about 8 times that of 11β-hydroxyprogesterone. In addition, whereas 9α-fluoro-11β-hydroxyprogesterone has pronounced mineralocorticoid effects, BKP lacks such effects. BKP has been described as a weaker progestogen. It has been used at doses of as much as 300 mg orally per day. In addition to its activity as a progestogen, BKP has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
