Multiple presynaptic metabotropic glutamate receptors modulate excitatory and inhibitory synaptic transmission in hippocampal area CA1

摘要: The metabotropic glutamate receptors (mGluRs) have many important roles in regulation of neuronal excitability and synaptic transmission. In hippocampal area CA1, activation mGluRs can reduce both excitatory inhibitory conventional view is that the presynaptic effects are mediated by L-2-amino-4-phosphonobutyric acid (L-AP4)-sensitive, or group III (mGluR4, mGluR6, mGluR7, mGluR8). However, some studies suggest other mGluR subtypes may also be involved transmission CA1. We found two pharmacologically distinct depression at Schaffer collateral--CA1 synapse. Consistent with previous studies, one receptor subtype an L-AP4-sensitive similar to mGluR4 mGluR7. we a second subtype, which mGluR1 mGluR5 (group I mGluRs), Analysis agonists these on miniature EPSCs paired-pulse facilitation localized presynaptically. It shown reduces synapses CA1 presynaptically localized, insensitive L-AP4, sensitive selective for mGluR5.