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Galantamine (Nivalin, Razadyne, Razadyne ER, Reminyl, Lycoremine) is used for the treatment of mild to moderate Alzheimer's disease and various other memory impairments, in particular those of vascular origin. It is an alkaloid that is obtained synthetically or from the bulbs and flowers of ''Galanthus caucasicus'' (Caucasian snowdrop, Voronov's snowdrop), ''Galanthus woronowii'' (Amaryllidaceae) and related genera like ''Narcissus'' (daffodil), ''Leucojum aestivum'' (snowflake), and ''Lycoris'' including ''Lycoris radiata'' (Red Spider Lily).〔(NNFCC Project Factsheet: Sustainable Production of the Natural Product Galanthamine (Defra), NF0612 )〕 Studies of usage in modern medicine began in the Soviet Union in the 1950s. The active ingredient was extracted, identified, and studied, in particular in relation to its acetylcholinesterase (AChE)-inhibiting properties. The bulk of the work was carried out by Soviet pharmacologists M. D. Mashkovsky and R. P. Kruglikova–Lvova, beginning in 1951. The work of Mashkovsky and Kruglikova-Lvova was the first published work that demonstrated the AChE-inhibiting properties of galantamine. The first industrial process was developed in Bulgaria by prof. Paskov in 1959 (Nivalin, Sopharma) from a species traditionally used as a popular medicine in Eastern Europe, and, thus, the idea for developing a medicine from these species seems to be based on the local use (i.e., an ethnobotany-driven drug discovery). Galantamine has been used for decades in Eastern Europe and Russia for various indications such as treatment of myasthenia, myopathy, and sensory and motor dysfunction associated with disorders of the central nervous system. In the US, it is FDA approved for the treatment of Alzheimer's disease. It is available in both a prescription form and as an over the counter supplement. == Pharmacology == Galantamine is a potent allosteric potentiating ligand of human nicotinic acetylcholine receptors (nAChRs) α4β2, α7/5-HT3, α3β4, and α6β4 in certain areas of the brain, as well as a weak competitive and reversible cholinesterase inhibitor in all areas of the body. It increases the concentration and thereby action of acetylcholine in certain parts of the brain. It has shown activity in modulating the nicotinic cholinergic receptors on cholinergic neurons to increase acetylcholine release. It is hypothesized that this action might relieve some of the symptoms of Alzheimer's. Galantamine in its pure form is a white powder. The atomic resolution 3D structure of the complex of galantamine and its target, acetylcholinesterase, was determined by X-ray crystallography in 1999 (PDB code: (1DX6 ); (see complex )). There is no evidence that galantamine alters the course of the underlying dementing process.〔(Ortho-McNeil Neurologics, "Razadyne ER US Product Insert", May 2006 )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Galantamine」の詳細全文を読む スポンサード リンク
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