Nicotine addiction phenotypes in a BAC transgenic mouse model overexpressing the CHRNA5/A3/B4 genomic cluster

The CHRNA5/A3/B4 genomic cluster encodes for the alpha5, alpha3 and beta4 subunits of the nicotinic acetylcholine receptors (nAChRs). Human genetic studies have revealed a significant association of variants in this genomic region with nicotine dependence. However, the mechanisms through which overe...

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Detalles Bibliográficos
Autor: Molas Casacuberta, Susanna
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2012
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/104155
Acceso en línea:http://hdl.handle.net/10803/104155
Access Level:acceso abierto
Palabra clave:Nicotine addiction
Cluster CHRNA5/A3/B4
nAChRs
Cognition
Hippocampus
Neural plasticity
Medial habenula
Adicció a la nicotina
Cognició
Hipocamp
Plasticitat neuronal
Habenula medial
616.89
Descripción
Sumario:The CHRNA5/A3/B4 genomic cluster encodes for the alpha5, alpha3 and beta4 subunits of the nicotinic acetylcholine receptors (nAChRs). Human genetic studies have revealed a significant association of variants in this genomic region with nicotine dependence. However, the mechanisms through which overexpression of these three subunits may influence smoking-related behaviours is not understood. To gain insight in the possible mechanisms, we used a BAC transgenic mouse model overexpressing this cluster containing the three genes together with their transcriptional regulatory elements. We found that overexpression of the cluster: i) increases sensitivity to the pharmacological effects of nicotine; ii) modifies particular cognitive domains associated to drug addiction and hippocampal neuronal complexity and synaptic plasticity; and iii) shifts the rewarding and aversive properties of nicotine and the manifestation of nicotine-withdrawal syndrome. Our study suggests that the genomic cluster CHRNA5/A3/B4 contributes to genetic vulnerability to nicotine addiction and promotes smoking-related behaviours possibly through hippocampal plasticity changes.