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An isolated brain is a brain kept alive in vitro, either by perfusion by a blood substitute, often an oxygenated solution of various salts, or by submerging the brain in oxygenated artificial cerebrospinal fluid (CSF).〔von Bohlen and Halbach O. The isolated mammalian brain: an in vivo preparation suitable for pathway tracing. Eur J Neurosci. 1999 Mar;11(3):1096-100. PMID 10103102〕 It is the biological counterpart of brain in a vat. A related concept, attaching the brain or head to the circulatory system of another organism, is called a head transplant. An isolated brain however is more typically attached to an artificial perfusion device rather than a biological body. The brains of many different organisms have been kept alive in-vitro for hours, or in some cases days. The central nervous system of invertebrate animals is often easily maintained as they need less oxygen and to a larger extent get their oxygen from CSF; for this reason their brains are more easily maintained without perfusion.〔Luksch H, Walkowiak W, Muñoz A, ten Donkelaar HJ. The use of in vitro preparations of the isolated amphibian central nervous system in neuroanatomy and electrophysiology. J Neurosci Methods. 1996 Dec;70(1):91–102. PMID 8982986〕 Mammalian brains on the other hand have a much lesser degree of survival without perfusion and an artificial blood perfusate is usually used. For methodological reasons, most research on isolated mammalian brains has been done with guinea pigs. These animals have a significantly larger basilar artery (a major artery of the brain) compared to rats and mice, which makes cannulation (to supply CSF) much easier. == History == * 1812 – Julien Jean César Le Gallois (a.k.a. Legallois) put forth the original idea for resuscitating severed heads through the use of blood transfusion.〔(Google Scholar:("Le Gallois" OR Legallois) 1812 )〕 * 1818 – Mary Shelley published ''Frankenstein; or, the Modern Prometheus''. * 1836 – Astley Cooper showed in rabbits that compression of the carotid and vertebral arteries leads to death of an animal; such deaths can be prevented if the circulation of oxygenated blood to the brain is rapidly restored.〔(Accessory sources of blood supply to the brain of the cat )〕 * 1857 – Charles Brown-Sequard decapitated a dog, waited ten minutes, attached four rubber tubes to the arterial trunks of the head, and injected blood containing oxygen by means of a syringe. Two or three minutes later voluntary movements of the eyes and muscles of the muzzle resumed. After cessation of oxygenated blood transfusion movements stopped.〔(Brown-Sequard C. Recherches expérimentales sur les propriétés physiologique et les usages du sang rouge et du sang noir et de leurs principaux éléments gazeux, l'oxygène et l'acide carbonique. Journal de la physiologie l'homme et des animaux. 1858;1:95–122. 353–367, 729–735. )〕 * 1887 – Jean Baptiste Vincent Laborde made what appears to be first recorded attempt to revive the heads of executed criminals by connecting the carotid artery of the severed human head to the carotid artery of a large dog. According to Laborde's account, in isolated experiments a partial restoration of brain function was attained.〔 * 1912 – Corneille Heymans maintained life in an isolated dog's head by connecting the carotid artery and jugular vein of the severed head to the carotid artery and jugular vein of another dog. Partial functioning in the severed head was maintained for a few hours.〔(Heymans' biography )〕 * 1928 – Sergey Bryukhonenko showed life could be maintained in the severed head of a dog by connecting the carotid artery and jugular vein to an artificial circulation machine.〔http://www.sklifos.ru/OTDEL/otd39.htm〕 * 1963 – Robert J. White isolated the brain from one monkey and attached it to the circulatory system of another animal. 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「isolated brain」の詳細全文を読む スポンサード リンク
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