title: Astrocytes control GABAergic inhibition of neurons in the mouse barrel cortex.
abstract: Astrocytes in the barrel cortex respond with a transient Ca2+ increase to neuronal stimulation and this response is restricted to the stimulated barrel field. In the present study we suppressed the astrocyte response by dialysing these cells with the Ca2+ chelator BAPTA. Electrical stimulation triggered a depolarization in stellate or pyramidal ‘regular spiking' neurons from cortex layer 4 and 2/3 and this response was augmented in amplitude and duration after astrocytes were dialysed with BAPTA. Combined blockade of GABAA and GABAB receptors mimicked the effect of BAPTA dialysis, while glutamate receptor blockers had no effect. Moreover, the frequency of spontaneous postsynaptic currents was increased after BAPTA dialysis. Outside the range of BAPTA dialysis astrocytes responded with a Ca2+ increase, but in contrast to control, the response was no longer restricted to one barrel field. Our findings indicate that astrocytes control neuronal inhibition in the barrel cortex.
authors.affiliation: Max-Delbrück-Centre for Molecular Medicine, Cellular Neuroscience, Robert-Rössle-Str. 10, 13092 Berlin-Buch, Berlin, Germany. bruno.benedetti@mdc-berlin.de
authors.forename: B
authors.initials: B
authors.lastname: Benedetti
authors.forename: V
authors.initials: V
authors.lastname: Matyash
authors.forename: H
authors.initials: H
authors.lastname: Kettenmann
mesh_terms: D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004558:Electric Stimulation; D058788:GABA-B Receptor Antagonists / Q000494:pharmacology; D007150:Immunohistochemistry; D051379:Mice; D008822:Mice, Transgenic; D009415:Nerve Net / Q000187:drug effects / Q000378:metabolism; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D010721:Phosphinic Acids / Q000494:pharmacology; D011412:Propanolamines / Q000494:pharmacology; D011724:Pyridazines / Q000494:pharmacology; D011963:Receptors, GABA-A / Q000378:metabolism; D018080:Receptors, GABA-B / Q000378:metabolism; D013003:Somatosensory Cortex / Q000187:drug effects / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D058788:GABA-B Receptor Antagonists; D010721:Phosphinic Acids; D011412:Propanolamines; D011724:Pyridazines; D011963:Receptors, GABA-A; D018080:Receptors, GABA-B; C085075:CGP 55845A; D004533:Egtazic Acid; D005680:gamma-Aminobutyric Acid; C049853:gabazine; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid