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High-throughput Screening for Small-molecule Modulators of Inward Rectifier Potassium Channels
Published on: January 27, 2013
Acoplamiento promiscuo entre el receptor de sulfonilurea y los canales de potasio que se rectifican hacia adentro
C Ammälä1, A Moorhouse, F Gribble
1University Laboratory of Physiology, Oxford, UK.
Nature
|February 8, 1996
Resumen
Los receptores de sulfonilurea (SUR) permiten que los fármacos sulfonilureados regulen la secreción de insulina al interactuar con los canales de potasio. El propio SUR carece de actividad de canal, pero sensibiliza otros canales K a las sulfonilureas, no necesariamente al ATP.
Área de la Ciencia:
- Farmacología Farmacología.
- Biología Molecular Biología Molecular
- Endocrinología Endocrinología.
Sus antecedentes:
- Las sulfonilureas son medicamentos clave para la diabetes mellitus no dependiente de la insulina.
- Su mecanismo consiste en unirse a los receptores de sulfonilurea (SUR) en las células beta pancreáticas, inhibiendo los canales de potasio sensibles al ATP (K-ATP) y estimulando la liberación de insulina.
- Existe un debate significativo con respecto a la relación precisa entre SUR, los canales K-ATP y la atribución de la sensibilidad al ATP.
Objetivo del estudio:
- Para aclarar el papel funcional del receptor de sulfonilurea (SUR).
- Para determinar si SUR posee actividad de canal intrínseco.
- Investigar si el SUR confiere sensibilidad a la sulfonilurea y/o sensibilidad al ATP a otros canales de potasio.
Principales métodos:
- Investigó las propiedades funcionales de SUR en el contexto de la modulación de los canales de potasio.
- Examinó la interacción entre SUR y varios canales de potasio de rectificación interna.
- Evaluó el impacto de SUR en la sensibilidad del canal a las sulfonilureas y el ATP.
Principales resultados:
- Demostrado que SUR no posee actividad de canal intrínseca.
- Se demostró que el SUR confiere sensibilidad a la sulfonilurea a varios tipos de canales K de rectificación interna.
- Se encontró que el SUR no necesariamente confiere sensibilidad al ATP a estos canales K modulados.
Conclusiones:
- SUR actúa como una subunidad reguladora que confiere la sensibilidad de la sulfonilurea a canales de potasio específicos.
- El mecanismo de acción de la sulfonilurea no se basa únicamente en la modulación directa de la sensibilidad al ATP por SUR.
- Esto aclara la base molecular de la secreción de insulina inducida por sulfonilurea, diferenciando el papel de SUR de la subunidad formadora de poros.
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