Control of Glutamate Clearance and Synaptic Efficacy by Glial Coverage of Neurons

• Published in: Science (American Association for the Advancement of Science) 2001-05, Vol.292 (5518), p.923-926
• Main Authors: Stéphane H. R. Oliet, Piet, Richard, Poulain, Dominique A.
• Format: Article
• Language: English
• Subjects: Amino Acid Transport System X-AG; Amino acid transport system XAG; Aminobutyrates - pharmacology; Aminobutyric Acids; Anatomy; Animals; Astrocytes; Astrocytes - physiology; ATP-Binding Cassette Transporters; ATP-Binding Cassette Transporters - antagonists & inhibitors; ATP-Binding Cassette Transporters - metabolism; Biological and medical sciences; Cells; Cellular biology; Central nervous system; Dicarboxylic Acids; Dicarboxylic Acids - pharmacology; Electrophysiology; Excitatory Amino Acid Agonists; Excitatory Amino Acid Agonists - pharmacology; Excitatory Amino Acid Antagonists; Excitatory Amino Acid Antagonists - pharmacology; Excitatory Postsynaptic Potentials; Female; Fundamental and applied biological sciences. Psychology; Glutamate; Glutamate receptors; Glutamic Aci; Glutamic Acid - metabolism; Hypothalamic hormones; In Vitro Techniques; Inhibition; Lactation; Life Sciences; Nervous system; Neural transmission; Neurons; Neurons - physiology; Neurons and Cognition; Neuroscience; Neurotransmitter Uptake Inhibitors - pharmacology; Neurotransmitters; Pyrrolidines - pharmacology; Radio transmitters; Rats; Rats, Wistar; Receptors, AMPA - antagonists & inhibitors; Receptors, AMPA - metabolism; Receptors, Metabotropic Glutamate - metabolism; Supraoptic Nucleus - cytology; Supraoptic Nucleus - physiology; Synapses - physiology; Synaptic transmission; Synaptic Transmission - drug effects; Vertebrates: nervous system and sense organs
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1059162

Analysis of excitatory synaptic transmission in the rat hypothalamic supraoptic nucleus revealed that glutamate clearance and, as a consequence, glutamate concentration and diffusion in the extracellular space, is associated with the degree of astrocytic coverage of its neurons. Reduction in glutamate clearance, whether induced pharmacologically or associated with a relative decrease of glial coverage in the vicinity of synapses, affected transmitter release through modulation of presynaptic metabotropic glutamate receptors. Astrocytic wrapping of neurons, therefore, contributes to the regulation of synaptic efficacy in the central nervous system.