G protein-coupled receptor signalling in astrocytes in health and disease: A focus on metabotropic glutamate receptors

Department of Cell Physiology and Pharmacology, College of Medicine, Biological Science & Psychology, University of Leicester, University Road, Leicester, LE1 9HN, United Kingdom.
Biochemical pharmacology (Impact Factor: 5.01). 04/2012; 84(3):249-59. DOI: 10.1016/j.bcp.2012.04.009
Source: PubMed


Work published over the past 10-15 years has caused the neuroscience community to engage in a process of constant re-evaluation of the roles of glial cells in the mammalian central nervous system. Recent emerging evidence suggests that, in addition to carrying out various homeostatic functions within the CNS, astrocytes can also engage in a two-way dialogue with neurons. Astrocytes possess many of the receptors, and some of the ion channels, present in neurons endowing them with an ability to sense and respond to an array of neuronal signals. In addition, an expanding number of small molecules and proteins have been shown to be released by astrocytes in both health and disease. In this commentary we will highlight advances in our understanding of G protein-coupled receptor signalling in astrocytes, with a particular emphasis on metabotropic glutamate (mGlu) receptors. Discussion will focus on the major mGlu receptors expressed in astrocytes, mGlu3 and mGlu5, how these receptors can influence different aspects of astrocyte physiology, and how signalling by these G protein-coupled receptors might change under pathophysiological circumstances.

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    • "Group I includes mGluR1 and mGluR5 subtypes, which are coupled to phosphoinositide hydrolysis [3] [4]. mGluR5 is expressed in both neurons and astrocytes and plays an important role in the regulation of the glio-neuronal cross-talk under both physiological and pathological conditions [5] [6] [7] [8]. Moreover, several lines of evidence indicate that mGluR5 is involved in early developmental processes, including proliferation, differentiation , and survival of neural progenitors ([9] [10] [11]; for review see [12]). "
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    ABSTRACT: The Concise Guide to PHARMACOLOGY 2013/14 provides concise overviews of the key properties of over 2000 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (, which provides more detailed views of target and ligand properties. The full contents can be found at G protein-coupled receptors are one of the seven major pharmacological targets into which the Guide is divided, with the others being G protein-coupled receptors, ligand-gated ion channels, ion channels, catalytic receptors, nuclear hormone receptors, transporters and enzymes. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. A new landscape format has easy to use tables comparing related targets. It is a condensed version of material contemporary to late 2013, which is presented in greater detail and constantly updated on the website, superseding data presented in previous Guides to Receptors and Channels. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and the Guide to Receptors and Channels, providing a permanent, citable, point-in-time record that will survive database updates.
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