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Midodrine
Midodrine, sold under the brand names ProAmatine and Orvaten among others, is an antihypotensive medication used to treat orthostatic hypotension (low blood pressure when standing) and urinary incontinence. It is taken oral administration, by mouth. Side effects of midodrine include hypertension (high blood pressure), paresthesia, pruritus, itching, goosebumps, chills, urinary urgency, urinary retention, and urinary frequency. Midodrine is a prodrug of its active metabolite desglymidodrine. This metabolite acts as a binding selectivity, selective agonist of the alpha-1 adrenergic receptor, α1-adrenergic receptor. This in turn results in vasoconstriction and increased blood pressure. Midodrine was discovered by 1971 and was introduced for medical use in the United States in 1996. Medical uses Midodrine is indicated for the treatment of symptomatic orthostatic hypotension. It can reduce dizziness and faints by about a third, but can be limited by troublesome goose bumps, prur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desglymidodrine
Desglymidodrine (developmental code name ST-1059) is the active metabolite of the prodrug antihypotensive agent midodrine. It acts as a binding selectivity, selective alpha-1 adrenergic receptor, α1-adrenergic receptor agonist. Desglymidodrine is formed from midodrine via glycine, deglycination. Chemistry Desglymidodrine, also known as 3,6-dimethoxy-β-hydroxy-2-phenylethylamine, is a substituted phenethylamine chemical derivative, derivative. Midodrine's experimental partition coefficient, log P is -0.5 and its predicted log P ranges from -0.49 to -0.95. The predicted log P of desglymidodrine ranges from -0.01 to 0.15. An structural analog, analogue of desglymidodrine is dimetofrine (3,5-dimethoxy-4,β-dihydroxy-''N''-methylphenethylamine). References {{Phenethylamines Alpha-1 adrenergic receptor agonists Antihypotensive agents Cardiac stimulants Human drug metabolites Methoxyphenethylamines Peripherally selective drugs Phenol ethers Phenylethanolamines Sympathomim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurogenic Orthostasis
Orthostatic hypotension, also known as postural hypotension, is a medical condition wherein a person's blood pressure drops when they are standing up ( orthostasis) or sitting down. Primary orthostatic hypotension is also often referred to as neurogenic orthostatic hypotension. The drop in blood pressure may be sudden ( vasovagal orthostatic hypotension), within 3 minutes (classic orthostatic hypotension) or gradual (delayed orthostatic hypotension). It is defined as a fall in systolic blood pressure of at least 20 mmHg or diastolic blood pressure of at least 10 mmHg after 3 minutes of standing. It occurs predominantly by delayed (or absent) constriction of the lower body blood vessels, which is normally required to maintain adequate blood pressure when changing the position to standing. As a result, blood pools in the blood vessels of the legs for a longer period, and less is returned to the heart, thereby leading to a reduced cardiac output and inadequate blood flow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Droxidopa
Droxidopa, also known as L-''threo''-dihydroxyphenylserine (L-DOPS) and sold under the brand names Northera and Dops among others, is sympathomimetic medication which is used in the treatment of hypotension (low blood pressure) and for other indications. It is taken by mouth. Side effects of droxidopa include headache, dizziness, nausea, and hypertension, among others. Droxidopa is a synthetic amino acid precursor which acts as a prodrug to the neurotransmitter norepinephrine (noradrenaline). Hence, it acts as a non-selective agonist of the α- and β-adrenergic receptors. Unlike norepinephrine, but similarly to levodopa (L-DOPA), droxidopa is capable of crossing the protective blood–brain barrier (BBB). Droxidopa was first described by 1971. It was approved for use in Japan in 1989 and was introduced in the United States in 2014. Medical uses Droxidopa is approved for use in the treatment of orthostatic hypotension, intradialytic hypotension (IDH; hemodialysis-induce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binding Selectivity
In chemistry, binding selectivity is defined with respect to the binding of ligands to a substrate forming a complex. Binding selectivity describes how a ligand may bind more preferentially to one receptor than another. A selectivity coefficient is the equilibrium constant for the reaction of displacement by one ligand of another ligand in a complex with the substrate. Binding selectivity is of major importance in biochemistry and in chemical separation processes. Selectivity coefficient The concept of selectivity is used to quantify the extent to which one chemical substance, A, binds each of two other chemical substances, B and C. The simplest case is where the complexes formed have 1:1 stoichiometry. Then, the two interactions may be characterized by equilibrium constants and .The constant used here are ''association'' constants. ''Dissociation'' constants are used in some contexts. A dissociation constant is the reciprocal of an association constant. \begin \ce;& \quad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urinary Frequency
Frequent urination, or urinary frequency (sometimes called pollakiuria), is the need to urinate more often than usual. Diuretics are medications that increase urinary frequency. Nocturia is the need of frequent urination at night. The most common cause of this condition for women and children is a urinary tract infection. The most common cause of urinary frequency in older men is an enlarged prostate. Frequent urination is strongly associated with frequent incidents of urinary urgency, which is the sudden need to urinate. It is often, though not necessarily, associated with urinary incontinence and polyuria (large total volume of urine). However, in other cases, urinary frequency involves only normal volumes of urine overall. Definition The normal number of times varies according to the age of the person. Among young children, urinating 8 to 14 times each day is typical. This decreases to 6–12 times per day for older children, and to 4–6 times per day among teenagers. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prodrug
A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be used to improve how the drug is absorbed, distributed, metabolized, and excreted (ADME). Prodrugs are often designed to improve bioavailability when a drug itself is poorly absorbed from the gastrointestinal tract. A prodrug may be used to improve how selectively the drug interacts with cells or processes that are not its intended target. This reduces adverse or unintended effects of a drug, especially important in treatments like chemotherapy, which can have severe unintended and undesirable side effects. History Many herbal extracts historically used in medicine contain glycosides (sugar derivatives) of the active agent, which are hydrolyzed in the intestines to release the active and more bioavailable aglycone. For example, sal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Metabolite
An active metabolite, or pharmacologically active metabolite is a biologically active metabolite of a xenobiotic substance, such as a drug or environmental chemical. Active metabolites may produce therapeutic effects, as well as harmful effects. Metabolites of drugs An active metabolite results when a drug is metabolized by the body into a modified form which produces effects in the body. Usually these effects are similar to those of the parent drug but weaker, although they can still be significant (see e.g. 11-hydroxy-THC, morphine-6-glucuronide). Certain drugs such as codeine and tramadol have metabolites (morphine and ''O''-desmethyltramadol respectively) that are stronger than the parent drug and in these cases the metabolite may be responsible for much of the therapeutic action of the parent drug. Sometimes, however, metabolites may produce toxic effects and patients must be monitored carefully to ensure they do not build up in the body. This is an issue with some well ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolite
In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, catalytic activity of their own (usually as a cofactor to an enzyme), defense, and interactions with other organisms (e.g. pigments, odorants, and pheromones). A primary metabolite is directly involved in normal "growth", development, and reproduction. Ethylene exemplifies a primary metabolite produced large-scale by industrial microbiology. A secondary metabolite is not directly involved in those processes, but usually has an important ecological function. Examples include antibiotics and pigments such as resins and terpenes etc. Some antibiotics use primary metabolites as precursors, such as actinomycin, which is created from the primary metabolite tryptophan. Some sugars are metabolites, such as fructose or glucose, which ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasoconstriction
Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vessels. The process is particularly important in controlling hemorrhage and reducing acute blood loss. When blood vessels constrict, the flow of blood is restricted or decreased, thus retaining body heat or increasing vascular resistance. This makes the skin turn paler because less blood reaches the surface, reducing the radiation of heat. On a larger level, vasoconstriction is one mechanism by which the body regulates and maintains mean arterial pressure. Medications causing vasoconstriction, also known as vasoconstrictors, are one type of medicine used to raise blood pressure. Generalized vasoconstriction usually results in an increase in systemic blood pressure, but it may also occur in specific tissues, causing a localized reduction in b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-1 Adrenergic Receptor
alpha-1 (α1) adrenergic are G protein-coupled receptors (GPCRs) associated with the Gq alpha subunit, Gq heterotrimeric G protein. α1-adrenergic receptors are subdivided into three highly homologous subtypes, i.e., α1A-adrenergic, α1A-, α1B-adrenergic, α1B-, and α1D-adrenergic, α1D-adrenergic receptor subtypes. There is no α1C receptor. At one time, there was a subtype known as α1C, but it was found to be identical to the previously discovered α1A receptor subtype. To avoid confusion, naming was continued with the letter D. Catecholamines like norepinephrine (noradrenaline) and epinephrine (adrenaline) signal through the α1-adrenergic receptors in the central nervous system, central and peripheral nervous systems. The crystal structure of the α1B-adrenergic receptor subtype has been determined in complex with the inverse agonist (+)-cyclazosin. Effects The α1-adrenergic receptor has several general functions in common with the Alpha-2 adrenergic receptor, α2-adrene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
