Different relevance of inactivation and F468 residue in the mechanisms of hEag1 channel blockage by astemizole, imipramine and dofetilide

The relevance of a point mutation at the C-terminal end of the S6 helix (F468) and the introduction of C-type inacti vation in the blockage of hEag1 channels by astemizole, imipra mine and dofetilide was tested. C-type inactivation decreased block by astemizole and dofetilide but not imipramine, sug...

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Detalles Bibliográficos
Autores: Gómez Varela, David, Contreras Jurado, Silvia Constanza, Furini, Simone, García Ferreiro, Rafael, Stühmer, Walter, Pardo, Luis A.
Tipo de recurso: artículo
Fecha de publicación:2006
País:España
Institución:Universidad Alfonso X el Sabio
Repositorio:Repositorio Institucional de la Universidad Alfonso X el Sabio
Idioma:inglés
OAI Identifier:oai:archive.uax.com:20.500.12080/26187
Acceso en línea:https://hdl.handle.net/20.500.12080/26187
Access Level:acceso abierto
Palabra clave:Two-electrode voltage clamp
Xenopus oocytes
Ether a` go-go
Potassium channels
Mutagenesis
Docking
Descripción
Sumario:The relevance of a point mutation at the C-terminal end of the S6 helix (F468) and the introduction of C-type inacti vation in the blockage of hEag1 channels by astemizole, imipra mine and dofetilide was tested. C-type inactivation decreased block by astemizole and dofetilide but not imipramine, suggest ing different binding sites in the channel. F468C mutation in creased IC50 for astemizole and imipramine but in contrast to HERG channels, only slightly for dofetilide. Together with mea surements on recovery of blocking, our observations indicate that the mechanism of hEag1 blockage by each of these drugs is dif ferent, and suggest relevant structural differences between hEag1 and HERG channels