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Efecto de los betabloqueantes en la disfunción contráctil cardíaca inducida por los radicales libres
1Klinik III für Innere Medizin and Klinik für Herz- und Thoraxchirurgie (M.S.) der Universität zu Köln, Cologne, Germany.
Circulation
|July 27, 1999
Resumen
Los radicales hidroxilo perjudican la contracción y la relajación del músculo cardíaco humano al inhibir la actividad de SERCA. El carvedilol y su metabolito BM-910228 están parcialmente protegidos contra esta disfunción inducida por el radical hidroxilo.
Área de la Ciencia:
- Cardiología Cardiología.
- La bioquímica es la bioquímica.
- Farmacología Farmacología.
Sus antecedentes:
- Los radicales hidroxilo (OH.) son también llamados radicales hidroxilo. están implicados en el daño cardiovascular.
- Los antagonistas de los receptores beta se usan para tratar afecciones cardíacas.
Objetivo del estudio:
- Investigar los efectos de los radicales hidroxilo en la contractilidad miocárdica humana y la actividad SERCA.
- Evaluar los efectos protectores del metoprolol, el carvedilol y su metabolito BM-910228 contra el daño inducido por los radicales hidroxilo.
Principales métodos:
- El miocardio humano aislado se utilizó para evaluar la fuerza isométrica de la contracción.
- La actividad de la Ca(2+) -ATPasa del retículo sarcoplásmico (SERCA) se midió en preparaciones de la membrana miocárdica.
- Se examinaron los efectos de los radicales hidroxilo y los antagonistas de los receptores beta.
Principales resultados:
- Los radicales hidroxilo disminuyeron la fuerza de contracción basal y aumentaron la tensión diastólica.
- Los radicales hidroxilo redujeron la respuesta inotrópica al calcio y abolieron la relación fuerza-frecuencia.
- El carvedilol y el BM-910228 atenuaron la disfunción contráctil inducida por el radical hidroxilo y preservaron la actividad SERCA, mientras que el metoprolol no tuvo un efecto significativo.
Conclusiones:
- Los radicales hidroxilo perjudican la contracción del miocardio humano, la relajación y la relación fuerza-frecuencia al inhibir SERCA.
- El carvedilol y su metabolito BM-910228 ofrecen protección parcial contra la disfunción cardíaca inducida por el radical hidroxilo.
- Estos hallazgos pueden explicar los beneficios del carvedilol en la insuficiencia cardíaca sin afectar la densidad del receptor beta-adrenérgico.
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