Changes in [Ca2+]0 during anoxia in CNS white matter
Autor: | Bruce R. Ransom, Jaakko Jarvinen, Robert Fern, Kai Kaila, Angus M. Brown |
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Rok vydání: | 1998 |
Předmět: |
Central Nervous System
Oxygene chemistry.chemical_element Calcium 03 medical and health sciences 0302 clinical medicine medicine Extracellular Animals Axon Hypoxia Brain 030304 developmental biology computer.programming_language 0303 health sciences General Neuroscience Optic Nerve Anatomy Compound muscle action potential Rats Electrophysiology medicine.anatomical_structure chemistry Calibration Optic nerve Biophysics computer Microelectrodes 030217 neurology & neurosurgery Intracellular |
Zdroj: | Neuroreport. 9(9) |
ISSN: | 0959-4965 |
Popis: | Irreversible anoxic injury of axons in the rat optic nerve requires the presence of extracellular Ca2+. To test the hypothesis that Ca2+ enters an intracellular compartment during anoxia we monitored [Ca2+]0 in this CNS white matter tract using ion-sensitive microelectrodes. Periods of anoxia lasting 15 min resulted in a rapid, reversible increase in [Ca2+]0 accompanied by transient loss of nerve conduction. This increase in [Ca2+]0 was apparently the result of extracellular space shrinkage. Anoxic periods lasting 60 min resulted in an initial rise followed by a sustained fall in [Ca2+]0, indicative of net influx of Ca2+ into an intracellular compartment. Following reoxygenation after 60 min of anoxia, [Ca2+]0 slowly returned toward control levels but nerve conduction recovered incompletely, indicating irreversible loss of function. Removal of bath Ca2+ lowered [Ca2+]0 to about 100 microM, prevented the anoxia-induced fall in [Ca2+]0, and protected against irreversible loss of the compound action potential. |
Databáze: | OpenAIRE |
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