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Precondicionamiento en corazones de conejos inmaduros: el papel de los canales KATP
J E Baker1, P Holman, G J Gross
1Division of Cardiothoracic Surgery, Department of Pharmacology and Medical College of Wisconsin, Milwaukee, USA. jbaker@mcw.edu
Circulation
|March 9, 1999
Resumen
Los corazones inmaduros pueden protegerse de lesiones a través del precondicionamiento, pero solo si no están expuestos a hipoxia crónica desde el nacimiento. Este efecto cardioprotector involucra el canal KATP.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Cardiología Neonatal Cardiología Neonatal
- El precondicionamiento isquémico.
Sus antecedentes:
- El precondicionamiento isquémico ofrece protección a los corazones adultos en todas las especies.
- El potencial para el precondicionamiento de corazones inmaduros, su duración y los mecanismos subyacentes siguen siendo menos comprendidos.
Objetivo del estudio:
- Investigar si los corazones inmaduros, bajo condiciones normoxicas o hipoxicas crónicas, pueden someterse a un precondicionamiento.
- Determinar la ventana de tiempo para este efecto cardioprotector y el papel del canal KATP.
Principales métodos:
- Corazones de conejos inmaduros aislados (7-10 días de edad) fueron sometidos a diferentes ciclos de isquemia / reperfusión para el precondicionamiento.
- Luego, los corazones fueron expuestos a un período isquémico más largo, con la recuperación medida por la presión desarrollada del ventrículo izquierdo.
- Se evaluó el efecto del bloqueo del canal KATP y los diferentes tiempos de reperfusión.
Principales resultados:
- Los corazones inmaduros de Normoxic mostraron una recuperación significativa después de un ciclo de precondicionamiento, sin ningún beneficio adicional de tres ciclos.
- Corazones crónicamente inmaduros con hipoxia no mostraron una mejor recuperación con el precondicionamiento en comparación con los controles no precondicionados.
- La cardioprotección se perdió cuando el período de recuperación después del precondicionamiento se extendió a 30 minutos.
- El bloqueo del canal KATP abolió el efecto de precondicionamiento en los corazones normoxic.
Conclusiones:
- Los corazones inmaduros de entornos normoxic pueden ser precondicionados.
- Los corazones inmaduros expuestos a hipoxia crónica desde el nacimiento no pueden ser precondicionados de manera efectiva.
- El canal KATP está implicado en el precondicionamiento de los corazones inmaduros normoxic.
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