Mechanisms of Brain Survival in Anoxia: Mitochondrial Activity and Ion Homeostasis in Turtle and Rat
When mammalian brain is deprived of oxygen, degenerative changes occur so rapidly that within a few minutes, recovery becomes questionable. This vulnerability is a general characteristic of vertebrates and is likely a function of the high energy demand of brain tissues. During anoxia, brain electrical activity ceases within seconds, transmembrane ion homeostasis is lost soon thereafter and energy reserves are depleted within a few minutes. The ultimate causes of functional loss and tissue damage are difficult to investigate because of the rapidity of these events and most investigations have been confined to detailing the pathways of aerobic and anaerobic glycolysis and the changes in substrates and intermediates that occur during hypoxia or anoxia.
KeywordsCytochrome Oxidase Mammalian Brain Anaerobic Glycolysis Extracellular Potassium Tissue Oxygen Tension
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