title: Kainate receptor-mediated depression of glutamatergic transmission involving protein kinase A in the lateral amygdala.
abstract: Kainate receptors (KARs) have been described as modulators of synaptic transmission at different synapses. However, this role of KARs has not been well characterized in the amygdala. We have explored the effect of kainate receptor activation at the synapse established between fibers originating at medial geniculate nucleus and the principal cells in the lateral amygdala. We have observed an inhibition of evoked excitatory postsynaptic currents (eEPSCs) amplitude after a brief application of KARs agonists KA and ATPA. Paired-pulse recordings showed a clear pair pulse facilitation that was enhanced after KA or ATPA application. When postsynaptic cells were loaded with BAPTA, the depression of eEPSC amplitude observed after the perfusion of KAR agonists was not prevented. We have also observed that the inhibition of the eEPSCs by KARs agonists was prevented by protein kinase A but not by protein kinase C inhibitors. Taken together our results indicate that KARs present at this synapse are pre-synaptic and their activation mediate the inhibition of glutamate release through a mechanism that involves the activation of protein kinase A.
authors.affiliation: Laboratorio de Neurociencia Celular y Plasticidad, Departamento de Fisiología, Anatomía y Biología Celular, Universidad Pablo de Olavide, Sevilla, Spain.
authors.forename: José Vicente
authors.initials: JV
authors.lastname: Negrete-Díaz
authors.forename: Paloma
authors.initials: P
authors.lastname: Duque-Feria
authors.forename: Yuniesky
authors.initials: Y
authors.lastname: Andrade-Talavera
authors.forename: Miriam
authors.initials: M
authors.lastname: Carrión
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Flores
authors.forename: Antonio
authors.initials: A
authors.lastname: Rodríguez-Moreno
mesh_terms: D000679:Amygdala / Q000378:metabolism*; D000818:Animals; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D018698:Glutamic Acid / Q000378:metabolism*; D036881:Long-Term Synaptic Depression / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018092:Kainic Acid Receptors / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D017868:Cyclic AMP-Dependent Protein Kinases; D018698:Glutamic Acid; D018092:Kainic Acid Receptors