The effects of kainate and the glutamate agonist, AMPA, are not separable in rat neocortical cultures.
The excitotoxic and [3H]gamma-aminobutyric acid ([3H]GABA)-releasing effects of quisqualate, alpha-amino-3-hydroxy-4-methyl-5-isoxazolepropionic acid (AMPA), kainate (KA), and their combinations were examined in primary cultures of the rat cerebral cortex. [3H]GABA efflux was evoked by a 5 min exposure of preloaded cultures to the respective agonist(s) (0.5 mM each). Cell death was induced by a 24 h exposure of cells to 1 mM quisqualate, AMPA and/or KA, and was quantified by measuring lactic dehydrogenase leakage. When applied alone, each agonist induced remarkable [3H]GABA release and excitotoxic cell death. Simultaneous administration of AMPA or quisqualate and KA did not evoke stronger responses than KA alone. These results indicate that AMPA and KA receptors are located on the same cortical cells and may activate the same receptor channels and/or intracellular messengers.
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Department of Anatomy, Georg-August University, Göttingen, FRG.
Erdö
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D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D005260:Female; D007051:Ibotenic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D007608:Kainic Acid / Q000494:pharmacology*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology; D011247:Pregnancy; D016318:Quisqualic Acid / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D018091:Receptors, AMPA; D018092:Kainic Acid Receptors; D017981:Receptors, Neurotransmitter / Q000187:drug effects; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D007051:Ibotenic Acid; D007608:Kainic Acid; D007770:L-Lactate Dehydrogenase; D016318:Quisqualic Acid; D018091:Receptors, AMPA; D018092:Kainic Acid Receptors; D017981:Receptors, Neurotransmitter; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D005680:gamma-Aminobutyric Acid