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Glutamate Receptor Modulation Is Restricted to Synaptic Microdomains.

ABSTRACT: A diverse array of neuromodulators governs cellular function in the prefrontal cortex (PFC) via the activation of G-protein-coupled receptors (GPCRs). However, these functionally diverse signals are carried and amplified by a relatively small assortment of intracellular second messengers. Here, we examine whether two distinct G?i-coupled neuromodulators (norepinephrine and GABA) act as redundant regulators of glutamatergic synaptic transmission. Our results reveal that, within single dendritic spines of layer 5 pyramidal neurons, alpha-2 adrenergic receptors (?2Rs) selectively inhibit excitatory transmission mediated by AMPA-type glutamate receptors, while type B GABA receptors (GABA(B)Rs) inhibit NMDA-type receptors. We show that both modulators act via the downregulation of cAMP and PKA. However, by restricting the lifetime of active G?i, RGS4 promotes the independent control of these two distinct target proteins. Our findings highlight a mechanism by which neuromodulatory microdomains can be established in subcellular compartments such as dendritic spines.

SUBMITTER: Lur G

PROVIDER: S-EPMC4920052 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Glutamate Receptor Modulation Is Restricted to Synaptic Microdomains.

Lur Gyorgy G Higley Michael J MJ

Cell reports 20150702 2

A diverse array of neuromodulators governs cellular function in the prefrontal cortex (PFC) via the activation of G-protein-coupled receptors (GPCRs). However, these functionally diverse signals are carried and amplified by a relatively small assortment of intracellular second messengers. Here, we examine whether two distinct Gαi-coupled neuromodulators (norepinephrine and GABA) act as redundant regulators of glutamatergic synaptic transmission. Our results reveal that, within single dendritic s ...[more]

PMID: 26146087

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Glutamate Receptor Modulation Is Restricted to Synaptic Microdomains.

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Glutamate Receptor Modulation Is Restricted to Synaptic Microdomains.

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