X-Message-Number: 5405 From: (David L Evens) Newsgroups: sci.cryonics Subject: Re: Brain damage Date: 10 Dec 1995 01:22:55 GMT Message-ID: <4adcpf$> References: <> Isak Sebastian Lytting () wrote: : Why does irreversible brain damage occur so quickly after oxygen : supply is cut off? What exactly happens with the brain? The structure of an active brain (at normal physiological temeprature) appears to need a very large amount of energy to keep it stable. In fact, in a human, as much as half of all energy production may go on in the central nervous system. Without oxygen, this energy production ceases and certain toxic materials (such as lactic acid) begin to accumulate as cells attempt to use anaerobic mechanisms to produce some energy. The combination of a lack of energy and the production of additional toxins appears to both directly kill cells and cause small-scall damage to neurons fairly rapidly as the energy to maintain the highly unfavoured shape of neurons is unavailable. Some recent work suggests that much of the mechanical brain damage that occurs after prolonged lack of blood flow may be caused by the stress of the return of circulation, but this is difficult to test and apparently has only recently been suggested. -- ---------------------------+-------------------------------------------------- Ring around the neutron, | "OK, so he's not terribly fearsome. A pocket full of positrons,| But he certainly took us by surprise!" A fission, a fusion, +-------------------------------------------------- We all fall down! | "Was anybody in the Maqui working for me?" ---------------------------+-------------------------------------------------- "I'd cut down ever Law in England to get at the Devil!" "And what man could stand up in the wind that would blow once you'd cut down all the laws?" ------------------------------------------------------------------------------ e-mail will be posted as I see fit. ------------------------------------------------------------------------------ Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=5405