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La corriente de potasio inducida por la proteína G I(K,ACh) es constitutivamente activa en pacientes con fibrilación
D Dobrev1, A Friedrich, N Voigt
1Department of Pharmacology and Toxicology, Medical Faculty, Dresden University of Technology, Dresden, Germany. dobrev@rcs.urz.tu-dresden.de
Circulation
|December 7, 2005
Resumen
En la fibrilación auricular, una corriente de potasio activada por acetilcolina constitutivamente activa (I(K,ACh)) contribuye al aumento de la corriente de rectificador basal hacia adentro (IK1). El bloqueo de este I ((K,ACh) puede ofrecer una nueva estrategia terapéutica para la fibrilación auricular.
Área de la Ciencia:
- Cardiología Cardiología.
- Electrofisiología y electrofisiología.
- Biología Molecular Biología Molecular
Sus antecedentes:
- Los mecanismos moleculares subyacentes del aumento de la corriente del rectificador de fondo hacia adentro (IK1) en la fibrilación auricular (FA) siguen sin estar claros.
- Este estudio investiga el papel potencial de la acetilcolina (ACh) activada por la acetilcolina constitutivamente activa (ACh) en la conductividad basal mejorada observada en la FA crónica (FAc).
Objetivo del estudio:
- Para determinar si la acetilcolina constitutivamente activa (ACh) activada por I(K,ACh) contribuye a mejorar la conductividad basal en la fibrilación auricular crónica (FAc).
Principales métodos:
- Las corrientes de célula completa y de canal único se midieron en miocitos auriculares de pacientes con ritmo sinusal (SR) y FAC usando técnicas de abrazadera de voltaje.
- Para evaluar sus efectos inhibidores, se empleó el bloqueador selectivo de I ((K,ACh) tertiapina.
Principales resultados:
- La corriente basal de célula entera fue significativamente mayor en cAF en comparación con SR.
- La tertiapina demostró una mayor potencia en el bloqueo de I ((K,ACh) en cAF que en SR, lo que indica un mayor componente de corriente basal sensible a la tertiapina en cAF.
- Las grabaciones de un solo canal revelaron prominentes I ((K,ACh) constitutivamente activas en cAF, con una mayor probabilidad de canal abierto.
Conclusiones:
- El aumento de la corriente K + del rectificador basal hacia adentro en cAF se atribuye a la actividad aumentada de IK1 y a la actividad constitutiva activa I ((K,ACh).
- Dirigirse al bloqueo I ((K,ACh) presenta un nuevo enfoque terapéutico potencial para el manejo de la fibrilación auricular.
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