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N-methyl-D-aspartate-induced long-term depression is associated with a decrease in postsynaptic protein kinase C substrate phosphorylation in rat hippocampal slices.

Els J M van Dam·Bert Ruiter·Amer Kamal·Geert M J Ramakers·Willem Hendrik Gispen·Pierre N E de Graan
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Abstract

Incubation of rat hippocampal slices with a low concentration of N-methyl-D-aspartate (NMDA; 20 microM; 3 min) elicits a form of long-term depression (LTD). We used this chemical protocol to study the involvement of pre- and postsynaptic protein kinase/phosphatase activity in NMDA receptor-dependent LTD. We determined the phosphorylation states of a pre- and a postsynaptic protein kinase C substrate, B-50/growth-associated protein 43 (GAP43) and RC3, respectively, using quantitative immunoprecipitation. NMDA incubation resulted in a 2-amino-5-phosphonovalerate-sensitive long-lasting (>60 min) decrease in synaptic efficacy and a concomitant reduction in RC3 phosphorylation. B-50/GAP43 phosphorylation was unaffected. This suggests that NMDA-LTD, in contrast to low frequency-LTD, is only associated with activation of postsynaptic protein phosphatases.

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2-Amino-5-phosphonovalerateAnimalsCalmodulin-Binding ProteinsDown-RegulationExcitatory Amino Acid AntagonistsExcitatory Postsynaptic PotentialsGAP-43 ProteinHippocampusMaleN-MethylaspartateNerve Tissue ProteinsNeural InhibitionNeurograninNeuronal PlasticityPhosphorylationProtein Kinase CRatsRats, WistarReceptors, N-Methyl-D-AspartateSynapsesSynaptic TransmissionJournal Article

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Els J M van Dam, Bert Ruiter, Amer Kamal, Geert M J Ramakers, Willem Hendrik Gispen, Pierre N E de Graan. 2002-03-08. N-methyl-D-aspartate-induced long-term depression is associated with a decrease in postsynaptic protein kinase C substrate phosphorylation in rat hippocampal slices.. https://doi.org/10.1016/s0304-3940(02)00037-x

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