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Aumento de las cantidades de GRP94 del miocardio durante la fibrilación auricular sostenida: ¿una respuesta
M Vitadello1, J Ausma, M Borgers
1CNR Unit for Muscle Physiology and Physiopathology, Department of Biomedical Sciences, University of Padova, Padova, Italy.
Circulation
|May 23, 2001
Resumen
La fibrilación auricular crónica conduce a un aumento de la proteína regulada por la glucosa GRP94 en las células del corazón. Este aumento de GRP94 es reversible, lo que sugiere una respuesta celular protectora en las aurículas fibriladas.
Área de la Ciencia:
- Biología Cardiovascular Biología Cardiovascular
- Respuesta Celular al Estrés Respuesta Celular al Estrés
- Cardiología Molecular Cardiología Molecular
Sus antecedentes:
- La fibrilación auricular se asocia con cambios estructurales y fenotípicos en los cardiomiocitos.
- La proteína regulada por la glucosa GRP94 es crucial para la viabilidad celular y su papel en la fibrilación auricular no está claro.
Objetivo del estudio:
- Para investigar los cambios en la expresión de GRP94 en los cardiomiocitos auriculares durante la fibrilación auricular crónica.
- Para determinar si los niveles de GRP94 están alterados en modelos humanos y animales de fibrilación auricular.
Principales métodos:
- Análisis de la expresión de GRP94 en el miocardio auricular de cabras y humanos utilizando enfoques inmunológicos.
- Inducción y mantenimiento de la fibrilación auricular en cabras durante hasta 16 semanas, seguido de cardioversión.
- Análisis inmunohistoquímico para confirmar la localización del aumento de GRP94 dentro de los cardiomiocitos.
Principales resultados:
- Los niveles de GRP94 se duplicaron en los miocitos auriculares de cabra después de 4-16 semanas de fibrilación, volviendo a la normalidad después de la cardioversión.
- El aumento de GRP94 también se observó en muestras de fibrilación auricular humana.
- A diferencia de la calreticulina, el HSP70 inducible aumentó en las aurículas fibriladas, lo que sugiere una respuesta al estrés.
Conclusiones:
- Un aumento significativo y reversible de GRP94 ocurre en los miocitos auriculares durante la fibrilación auricular crónica.
- Esta regulación ascendente de GRP94 puede representar un mecanismo celular protector en respuesta a la fibrilación.
- Los hallazgos destacan el papel potencial de GRP94 en la respuesta adaptativa de los cardiomiocitos al estrés.
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