Pertussis toxin prevents presynaptic inhibition by kainate receptors of rat hippocampal [3H]GABA release

• Autor(a) principal: Cunha, Rodrigo A.
• Data de Publicação: 2000
• Outros Autores: Malva, João O., Ribeiro, J. A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10316/4841; https://doi.org/10.1016/S0014-5793(00)01272-2
• topic: Kainate receptor; G protein; Protein kinase C; Hippocampus

Kainate receptors are ionotropic receptors, also reported to couple to Gi/Go proteins, increasing neuronal excitability through disinhibition of neuronal circuits. We directly tested in hippocampal synaptosomes if kainate receptor-mediated inhibition of GABA release involved a metabotropic action. The kainate analogue, domoate (3 [mu]M), inhibited by 24% [3H]GABA-evoked release, an effect reduced by 76% in synaptosomes pre-treated with pertussis toxin. Protein kinase C inhibition attenuated by 82% domoate-induced inhibition of GABA release whereas protein kinase C activation did not change kainate receptor binding. Thus, domoate inhibition of GABA release recruits Gi/Go proteins and a protein kinase C pathway.