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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'' and ''Aphaenogaster'' ants. It is structurally similar to nicotine and anabasine. Similarly, it has been shown to act as an agonist on most nicotin ... References Isoxazoles Nicotinic agonists ... [...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 of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Α4β2 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 sensitivi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 produces extremely dangerous toxic nicotinic side effects. 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 its decreased potency and 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, tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Α7 Nicotinic Acetylcholine Receptor
The alpha-7 nicotinic receptor, also known as the α7 receptor, is a type of nicotinic acetylcholine receptor implicated in long-term memory, consisting entirely of α7 subunits.Pharmacology, (Rang, Dale, Ritter & Moore, , 5th ed., Churchill Livingstone 2003) p. 138. As with other nicotinic acetylcholine receptors, functional α7 receptors are pentameric stoichiometry.html" ;"title=".e., (α7)5 stoichiometry">.e., (α7)5 stoichiometry It is located in the brain, spleen, and lymphocytes of lymph nodes where activation yields Excitatory postsynaptic potential, post- and excitatory presynaptic potential, presynaptic excitation, mainly by increased Ca2+ permeability. Further, recent work has implicated this receptor as being important for generation of adult mammal neurons in the retina. Functional α7 receptors are present in the submucous plexus neurons of the guinea-pig ileum. Medical relevance Recent work has demonstrated a potential role in reducing inflammatory neurotoxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nootropics
Nootropics ( , or ) (colloquial: smart drugs and cognitive enhancers, similar to adaptogens) are a wide range of natural or synthetic supplements or drugs and other substances that are claimed to improve cognitive function or to promote relaxation, particularly boosting mood, executive functions, attention, memory, creativity, or motivation in healthy individuals. The use of cognition-enhancing supplements by healthy individuals in the absence of a medical indication spans numerous controversial issues, including the ethics and fairness of their use, concerns over adverse effects, and the diversion of prescription drugs for non-medical uses. Nonetheless, the international sales of cognitive- or mood-enhancing supplements have continued to grow over time and in 2012 reached 0.69 billion. With sales supported by global health trends, the market is expected to reach US$33.85 billion by the year 2030, at a CAGR of 14.8%. While most nootropics are not regulated, there are othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoxazoles
Isoxazole is an electron-rich azole with an oxygen atom next to the nitrogen. It is also the class of compounds containing this ring. Isoxazolyl is the univalent radical derived from isoxazole. Occurrence Isoxazole rings are found in some natural products, such as ibotenic acid and muscimol. Synthesis Isoxazole can be synthesised via a variety of methods. Examples include via a 1,3-dipolar cycloaddition of nitrile oxides with alkynes; or the reaction of hydroxylamine with 1,3-diketones or derivatives of propiolic acid. Photochemistry The photolysis of isoxazole was first reported in 1966. Due to the weak N-O bond, the isoxazole ring tends to collapse under UV irradiation, rearranging to oxazole through azirine intermediate. Meanwhile, the azirine intermediate can react with nucleophiles, especially carboxylic acids. Given the photoreactions, isoxazole group is developed as a native photo-cross-linker for photoaffinity labeling and chemoproteomic studies. Pharmaceuticals and he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anabaseine
Anabaseine (3,4,5,6-tetrahydro-2,3′-bipyridine) is an alkaloid toxin produced by '' Nemertines'' and ''Aphaenogaster'' ants. It is structurally similar to nicotine and anabasine. Similarly, it has been shown to act as an agonist on most nicotinic acetylcholine receptors in the central nervous system and peripheral nervous system. Mechanism of action The iminium form of anabaseine binds to most nicotinic acetylcholine receptors in both the peripheral nervous system and central nervous system. But, there is a higher binding affinity for receptors in the brain with a α7 subunit, as well as skeletal muscle receptors. Binding causes the depolarization of neurons, and induces the release of both dopamine and norepinephrine. Biological effects Anabaseine causes paralysis in crustaceans and insects, but not in vertebrates, presumably by acting as an agonist on peripheral neuromuscular nicotinic acetylcholine receptors. Structure The anabaseine molecule consists of a non-aromatic te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 definitions of nausea were proposed in a 2011 book on the topic. Nausea is a non-specific symptom, which means that it has many possible causes. Some common causes of nausea are gastroenteritis and other gastrointestinal disorders, food poisoning, motion sickness, dizziness, migraine, fainting, low blood sugar, anxiety, and lack of sleep. Nausea is a side effect of many medications including chemotherapy, or morning sickness in early pregnancy. Nausea may also be caused by disgust and depression. Medications taken to prevent and treat nausea and vomiting are called antiemetics. The most commonly prescribed antiemetics in the US are promethazine, metoclopramide, and the newer ondansetron. The word nausea is from Lat ... [...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 Agonists * Acetylcholine (endogenous neurotransmitter that binds non- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicotinic Acetylcholine Receptors
Nicotinic acetylcholine receptors, or nAChRs, are 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 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. The nicotinic receptors are considered choliner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5-HT3 Receptor
The 5-HT3 receptor belongs to the Cys-loop superfamily of ligand-gated ion channels (LGICs) and therefore differs structurally and functionally from all other 5-HT receptors (5-hydroxytryptamine, or serotonin receptors) which are G protein-coupled receptors. This ion channel is cation-selective and mediates neuronal depolarization and excitation within the central and peripheral nervous systems. As with other ligand gated ion channels, the 5-HT3 receptor consists of five subunits arranged around a central ion conducting pore, which is permeable to sodium (Na), potassium (K), and calcium (Ca) ions. Binding of the neurotransmitter 5-hydroxytryptamine (serotonin) to the 5-HT3 receptor opens the channel, which, in turn, leads to an excitatory response in neurons. The rapidly activating, desensitizing, inward current is predominantly carried by sodium and potassium ions. 5-HT3 receptors have a negligible permeability to anions. They are most closely related by homology to the nicotinic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abbott Laboratories
Abbott Laboratories is an American multinational medical devices and health care company with headquarters in Abbott Park, Illinois, United States. The company was founded by Chicago physician Wallace Calvin Abbott in 1888 to formulate known drugs; today, it sells medical devices, diagnostics, branded generic medicines and nutritional products. It split off its research-based pharmaceuticals business into AbbVie in 2013. The firm has also been present in India for over 100 years through its subsidiary Abbott India Limited, and it is currently India's largest healthcare products company. Among its well-known products across the medical devices, diagnostics, and nutrition product divisions are Pedialyte, Similac, BinaxNOW, Ensure, Glucerna, ZonePerfect, FreeStyle Libre, i-STAT and MitraClip. History Foundation and early history In 1888 at the age of 30, Wallace Abbott (1857–1921), an 1885 graduate of the University of Michigan, founded the Abbott Alkaloidal Company in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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