Intracellular calcium in NCB-20 cells: elevation by depolarization and ethanol but not by glutamate.
Intracellular Ca2+, measured in NCB-20 cells with the fluorescent indicator fura-2, was elevated by K(+)-depolarization and by ethanol, but not by the excitatory amino acids L-glutamate and N-methyl-D-aspartate. These amino acids failed to raise intracellular Ca2+ levels even in the presence of elevated extracellular Ca2+, in the absence of extracellular Mg2+ or Na+, under depolarizing conditions, or in differentiated cells, and induced neither 45Ca2+ uptake nor excitotoxic cell death. NCB-20 cells thus appear to express functional voltage-gated, but not N-methyl-D-aspartate receptor-gated, Ca2+ channels.
Department of Neurology, University of California, San Francisco 94110.
J
J
Chan
D A
DA
Greenberg
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002132:Calcium Radioisotopes; D002470:Cell Survival / Q000187:drug effects; D006224:Cricetinae; D000431:Ethanol / Q000494:pharmacology*; D016257:Fura-2; D005971:Glutamates / Q000494:pharmacology*; D018698:Glutamic Acid; D051379:Mice; D016202:N-Methylaspartate / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism*
D002132:Calcium Radioisotopes; D005971:Glutamates; D016194:Receptors, N-Methyl-D-Aspartate; D000431:Ethanol; D018698:Glutamic Acid; D016202:N-Methylaspartate; D002118:Calcium; D016257:Fura-2