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Epiboxidine
Epiboxidine is a chemical compound which acts as a partial agonist at neural nicotinic acetylcholine receptors, binding to both the α3β4 and the α4β2 subtypes. It was developed as a less toxic analogue of the potent frog-derived alkaloid epibatidine, which is around 200 times stronger than morphine as an analgesic but is deadly toxic. Epiboxidine is around one-tenth as potent as epibatidine as an α4β2 agonist, but has around the same potency as an α3β4 agonist. It has only one-tenth of the analgesic power of epibatidine, but is also much less toxic. Uses Despite reduced toxicity compared to epibatidine, epiboxidine itself is still too toxic to be developed as a drug for use in humans. It is used in scientific research and as a parent compound to derive newer analogues which may be safer and have greater potential for clinical development. See also * ABT-418 ABT-418 is a drug developed by Abbott, that has nootropic, neuroprotective and anxiolytic effects, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epibatidine
Epibatidine is a chlorinated alkaloid that is secreted by the Ecuadoran frog '' Epipedobates anthonyi'' and poison dart frogs from the ''Ameerega'' genus. It was discovered by John W. Daly in 1974, but its structure was not fully elucidated until 1992. Whether epibatidine occurs naturally remains controversial due to challenges in conclusively identifying the compound from the limited samples collected by Daly. By the time that high-resolution spectrometry was used in 1991, there remained less than one milligram of extract from Daly's samples, raising concerns about possible contamination. Samples from other batches of the same species of frog failed to yield epibatidine. Epibatidine is a neurotoxin that interferes with nicotinic and muscarinic acetylcholine receptors. These receptors are involved in the transmission of painful sensations, and in movement, among other functions. Epibatidine causes full body numbness, which can rapidly progress to full body paralysis. Do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-4 Beta-2 Nicotinic Receptor
The alpha-4 beta-2 nicotinic receptor, also known as the α4β2 receptor, is a type of nicotinic acetylcholine receptor implicated in learning, consisting of α4 and β2 subunits. It is located in the brain, where activation yields post- and presynaptic excitation, mainly by increased Na+ and K+ permeability. Stimulation of this receptor subtype is also associated with growth hormone secretion. People with the inactive CHRNA4 mutation Ser248Phe are an average of 10 cm (4 inches) shorter than average and predisposed to obesity. A 2015 review noted that stimulation of the α4β2 nicotinic receptor in the brain is responsible for certain improvements in attentional performance; among the nicotinic receptor subtypes, nicotine has the highest binding affinity at the α4β2 receptor (ki=1 ), which is also the primary biological target that mediates nicotine's addictive properties. The receptors exist in the two stoichiometries: *(α4)2(β2)3 receptors have high sensit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ABT-418
ABT-418 is a drug developed by Abbott, that has nootropic, neuroprotective and anxiolytic effects, and has been researched for treatment of both Alzheimer's disease and ADHD. It acts as an agonist at neural nicotinic acetylcholine receptors, subtype-selective binding with high affinity to the α4β2, α7/ 5-HT3, and α2β2 nicotinic acetylcholine receptors but not α3β4 receptors ABT-418 was reasonably effective for both applications and fairly well tolerated, but produced some side effects, principally nausea, and it is unclear whether ABT-418 itself will proceed to clinical development or if another similar drug will be used instead. See also * Epiboxidine * Anabaseine Anabaseine (3,4,5,6-tetrahydro-2,3′-bipyridine) is an alkaloid toxin produced by ''Nemertines'' worms and ''Aphaenogaster'' ants. It is structurally similar to nicotine and anabasine. Similarly, it has been shown to act as an agonist on most ni ... References Isoxazoles Nicotinic ago ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Partial Agonist
In pharmacology, partial agonists are drugs that bind to and activate a given Receptor (biochemistry), receptor, but have only partial Intrinsic activity, efficacy at the receptor relative to a full agonist. They may also be considered Ligand (biochemistry), ligands which display both agonistic and Receptor antagonist, antagonistic effects—when both a full agonist and partial agonist are present, the partial agonist actually acts as a competitive antagonist, competing with the full agonist for receptor occupancy and producing a net decrease in the receptor activation observed with the full agonist alone. Clinically, partial agonists can be used to activate receptors to give a desired submaximal response when inadequate amounts of the endogenous ligand are present, or they can reduce the overstimulation of receptors when excess amounts of the endogenous ligand are present. Some currently common drugs that have been classed as partial agonists at particular receptors include buspi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicotinic Acetylcholine Receptor
Nicotinic acetylcholine receptors, or nAChRs, are Receptor (biochemistry), receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral nervous system, muscle, and many other tissues of many organisms. At the neuromuscular junction they are the primary receptor in muscle for motor nerve-muscle communication that controls muscle contraction. In the peripheral nervous system: (1) they transmit outgoing signals from the presynaptic to the postsynaptic cells within the Sympathetic nervous system, sympathetic and parasympathetic nervous system, and (2) they are the receptors found on skeletal muscle that receive acetylcholine released to signal for muscular contraction. In the immune system, nAChRs regulate inflammatory processes and signal through distinct intracellular pathways. In insects, the cholinergic system is limited to the central nervous system. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ganglion Type Nicotinic Receptor
The alpha-3 beta-4 nicotinic receptor, also known as the α3β4 receptor and the ganglion-type nicotinic receptor,Pharmacology, (Rang, Dale, Ritter & Moore, , 5th ed., Churchill Livingstone 2003) p. 138. is a type of nicotinic acetylcholine receptor, consisting of α3 and β4 subunits. It is located in the autonomic ganglia and adrenal medulla, where activation yields post- and/or presynaptic excitation, mainly by increased Na+ and K+ permeability. As with other nicotinic acetylcholine receptors, the α3β4 receptor is pentameric α3)m(β4)n where m + n = 5 The exact subunit stoichiometry is not known and it is possible that more than one functional α3β4 receptor assembles in vivo with varying subunit stoichiometries. Ligands which inhibit the α3β4 receptor have been shown to modulate drug-seeking behavior, making α3β4 a promising target for the development of novel antiaddictive agents. Ligands Source: Agonists * Acetylcholine (endogenous neurotransmitter that b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analog (chemistry)
A structural analog, also known as a chemical analog or simply an analog, is a compound having a structure similar to that of another compound, but differing from it in respect to a certain component. It can differ in one or more atoms, functional groups, or substructures, which are replaced with other atoms, groups, or substructures. A structural analog can be imagined to be formed, at least theoretically, from the other compound. Structural analogs are often isoelectronic. Despite a high chemical similarity, structural analogs are not necessarily functional analogs and can have very different physical, chemical, biochemical, or pharmacological properties. In drug discovery, either a large series of structural analogs of an initial lead compound are created and tested as part of a structure–activity relationship study or a database is screened for structural analogs of a lead compound. Chemical analogues of illegal drugs are developed and sold in order to circumvent la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloid
Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids. Alkaloids are produced by a large variety of organisms including bacteria, fungus, fungi, Medicinal plant, plants, and animals. They can be purified from crude extracts of these organisms by acid-base extraction, or solvent extractions followed by silica-gel column chromatography. Alkaloids have a wide range of pharmacology, pharmacological activities including antimalarial medication, antimalarial (e.g. quinine), asthma, antiasthma (e.g. ephedrine), chemotherapy, anticancer (e.g. omacetaxine mepesuccinate, homoharringtonine), cholinomimetic (e.g. galantamine), vasodilation, vasodilatory (e.g. vincamine), Antiarrhythmic agent, antiarrhythmic (e.g. quinidine), analgesic (e.g. morphine), antibacterial (e.g. chelerythrine), and anti-diabetic, antihyperglycemic activities (e.g. berb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphine
Morphine, formerly also called morphia, is an opiate that is found naturally in opium, a dark brown resin produced by drying the latex of opium poppies (''Papaver somniferum''). It is mainly used as an analgesic (pain medication). There are multiple methods used to administer morphine: oral; sublingual administration, sublingual; via inhalation; intramuscular, injection into a muscle, Subcutaneous injection, injection under the skin, or injection into the spinal cord area; transdermal; or via rectal administration, rectal suppository. It acts directly on the central nervous system (CNS) to induce analgesia and alter perception and emotional response to pain. Physical and psychological dependence and tolerance may develop with repeated administration. It can be taken for both acute pain and chronic pain and is frequently used for pain from myocardial infarction, kidney stones, and during Childbirth, labor. Its maximum effect is reached after about 20 minutes when administ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analgesic
An analgesic drug, also called simply an analgesic, antalgic, pain reliever, or painkiller, is any member of the group of drugs used for pain management. Analgesics are conceptually distinct from anesthetics, which temporarily reduce, and in some instances eliminate, sensation, although analgesia and anesthesia are neurophysiologically overlapping and thus various drugs have both analgesic and anesthetic effects. Analgesic choice is also determined by the type of pain: For neuropathic pain, recent research has suggested that classes of drugs that are not normally considered analgesics, such as tricyclic antidepressants and anticonvulsants may be considered as an alternative. Various analgesics, such as many NSAIDs, are available over the counter in most countries, whereas various others are prescription drugs owing to the substantial risks and high chances of overdose, misuse, and addiction in the absence of medical supervision. Etymology The word ''analgesic'' derive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicotinic Agonists
A nicotinic agonist is a drug that mimics the action of acetylcholine (ACh) at nicotinic acetylcholine receptors (nAChRs). The nAChR is named for its affinity for nicotine. Examples include nicotine (by definition), acetylcholine (the endogenous agonist of nAChRs), choline, epibatidine, lobeline, varenicline and cytisine. History Nicotine has been known for centuries for its intoxicating effect. It was first isolated in 1828 from the tobacco plant by German chemists Posselt and Reimann. The discovery of positive effects from nicotine on animal memory was discovered by in vivo researches in the mid 1980s. Those researches led to a new era in studies of nicotinic acetylcholine receptor (nAChR) and their stimulation but until then the focus had mainly been on nicotine addiction. The development of nAChR agonists began in the early 1990s after the discovery of nicotine's positive effects. Some research showed a possible therapy option in preclinical researches. ABT-418 was one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
