GIRK currents in VTA dopamine neurons control the sensitivity of mice to cocaine-induced locomotor sensitization.
Proc Natl Acad Sci U S A
; 115(40): E9479-E9488, 2018 10 02.
Article
em En
| MEDLINE
| ID: mdl-30228121
ABSTRACT
GABABR-dependent activation of G protein-gated inwardly rectifying potassium channels (GIRK or KIR3) provides a well-known source of inhibition in the brain, but the details on how this important inhibitory pathway affects neural circuits are lacking. We used sorting nexin 27 (SNX27), an endosomal adaptor protein that associates with GIRK2c and GIRK3 subunits, to probe the role of GIRK channels in reward circuits. A conditional knockout of SNX27 in both substantia nigra pars compacta and ventral tegmental area (VTA) dopamine neurons leads to markedly smaller GABABR- and dopamine D2R-activated GIRK currents, as well as to suprasensitivity to cocaine-induced locomotor sensitization. Expression of the SNX27-insensitive GIRK2a subunit in SNX27-deficient VTA dopamine neurons restored GIRK currents and GABABR-dependent inhibition of spike firing, while also resetting the mouse's sensitivity to cocaine-dependent sensitization. These results establish a link between slow inhibition mediated by GIRK channels in VTA dopamine neurons and cocaine addiction, revealing a therapeutic target for treating addiction.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cocaína
/
Transtornos Relacionados ao Uso de Cocaína
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Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G
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Neurônios Dopaminérgicos
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Locomoção
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2018
Tipo de documento:
Article