PT - JOURNAL ARTICLE AU - Sean M. Gallagher AU - Christine A. Daly AU - Mark F. Bear AU - Kimberly M. Huber TI - Extracellular Signal-Regulated Protein Kinase Activation Is Required for Metabotropic Glutamate Receptor-Dependent Long-Term Depression in Hippocampal Area CA1 AID - 10.1523/JNEUROSCI.5407-03.2004 DP - 2004 May 19 TA - The Journal of Neuroscience PG - 4859--4864 VI - 24 IP - 20 4099 - http://www.jneurosci.org/content/24/20/4859.short 4100 - http://www.jneurosci.org/content/24/20/4859.full SO - J. Neurosci.2004 May 19; 24 AB - Activation of group 1 metabotropic glutamate receptors (mGluRs) induces long-term depression (LTD) of synaptic transmission that relies on dendritic protein synthesis. We investigated the signal transduction pathways required for mGluR-LTD to identify candidate mechanisms for mGluR regulation of synaptic protein synthesis. Our results demonstrate a role for extracellular signal-regulated protein kinase (ERK), a subclass of the mitogen-activated protein kinases (MAPKs), in mGluR-LTD in area CA1 of the rat hippocampus. Inhibitors of the upstream kinase of ERK, MAP/ERK kinase significantly reduce mGluR-LTD induced by the group 1 agonist dihydroxyphenylglycine (DHPG) and synaptic stimulation but do not affect NMDA receptor-dependent LTD. In contrast, inhibitors of p38 MAPK were ineffective against DHPG-induced LTD. Consistent with the role of ERK in mGluR-LTD, we observed that DHPG treatment of hippocampal slices (isolated CA1), at concentrations that induce LTD, results in a robust phosphorylation of ERK but not of p38 MAPK. These results point to ERK as an important regulator of mGluR-LTD and a potential mechanism for mGluR regulation of synaptic protein synthesis.