GluR5 kainate receptor activation in interneurons increases tonic inhibition of pyramidal cells.

Archive ouverte

Cossart, Rosa | Esclapez, Monique | Hirsch, June, C. | Bernard, Christophe | Ben-Ari, Yehezkel

Edité par CCSD ; Nature Publishing Group -

International audience. We studied the modulation of GABAergic inhibition by glutamate and kainate acting on GluR5-containing kainate receptors in the CA1 hippocampal region. Glutamate, kainate or ATPA, a selective agonist of GluR5-containing receptors, generates an inward current in inhibitory interneurons and cause repetitive action potential firing. This results in a massive increase of tonic GABAergic inhibition in the somata and apical dendrites of pyramidal neurons. These effects are prevented by the GluR5 antagonist LY 293558. Electrical stimulation of excitatory afferents generates kainate receptor-mediated excitatory postsynaptic currents (EPSCs) and action potentials in identified interneurons that project to the dendrites and somata of pyramidal neurons. Therefore glutamate acting on kainate receptors containing the GluR5 subunit may provide a protective mechanism against hyperexcitability.

Suggestions

Du même auteur

Presynaptic kainate receptors that enhance the release of GABA on CA1 hippocampal interneurons.

Archive ouverte | Cossart, Rosa | CCSD

International audience. We report that kainate receptors are present on presynaptic GABAergic terminals contacting interneurons and that their activation increases GABA release. Application of kainate increased the ...

Dendritic but not somatic GABAergic inhibition is decreased in experimental epilepsy.

Archive ouverte | Cossart, Rosa | CCSD

International audience. Impaired inhibition is thought to be important in temporal lobe epilepsy (TLE), the most common form of epilepsy in adult patients. We report that, in experimental TLE, spontaneous GABAergic ...

Interneurons targeting similar layers receive synaptic inputs with similar kinetics.

Archive ouverte | Cossart, Rosa | CCSD

International audience. GABAergic interneurons play diverse and important roles in controlling neuronal network dynamics. They are characterized by an extreme heterogeneity morphologically, neurochemically, and phys...

Chargement des enrichissements...