Occurrence of a large Ca2+-independent release of glutamate during anoxia in isolated nerve terminals (synaptosomes).
Isolated rat cerebral cortical synaptosomes made anoxic by addition of cyanide developed an inhibition of the Ca2+-dependent release of glutamate 2 min after the addition of the metabolic inhibitor when the intrasynaptosomal ATP/ADP ratio decreased below 1.7. In contrast, cyanide induced a continuous efflux of glutamate through a Ca2+-independent pathway that accounted for the release of 25% of total intrasynaptosomal glutamate in 5 min. The results suggest that a Ca2+-independent release of glutamate could be implicated in the neurotoxic action of this amino acid during anoxia.
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism*; D003486:Cyanides / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D004734:Energy Metabolism; D005971:Glutamates / Q000378:metabolism*; D018698:Glutamic Acid; D002534:Hypoxia, Brain / Q000378:metabolism*; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*
D003486:Cyanides; D005971:Glutamates; D018698:Glutamic Acid; D004533:Egtazic Acid; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D011188:Potassium; D002118:Calcium