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Mecanismo de la vasodilatación coronaria producida por la bradicininina
L R Pelc1, G J Gross, D C Warltier
1Department of Anesthesiology, Medical College of Wisconsin, Milwaukee 53226.
Circulation
|June 1, 1991
Resumen
La bradicinina aumenta el flujo sanguíneo al subendocardio del corazón al activar los receptores B2 y liberar el factor de relajación derivado del endotelio, un hallazgo clave para la investigación de la circulación coronaria.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Biología Vascular Biología Vascular
- Farmacología Farmacología.
Sus antecedentes:
- La bradicinina es un conocido vasodilatador en la circulación cerebral.
- Sus efectos sobre la perfusión regional en la circulación coronaria canina no se habían estudiado previamente.
Objetivo del estudio:
- Para investigar el mecanismo de la vasodilatación coronaria inducida por la bradicinina.
- Determinar las funciones de la ciclooxigenasa, los receptores de bradicinina B2 y el factor de relajación derivado del endotelio (EDRF).
Principales métodos:
- Infusión intracoronaria de bradicinina en perros anestesiados para aislar los efectos sobre el flujo coronario.
- Uso de microesferas radiactivas para medir el flujo sanguíneo regional.
- Intervenciones farmacológicas: indometacina, antagonista de los receptores B2, inhibidores de la EDRF (quinacrina, L-arginina).
Principales resultados:
- La bradicinina aumentó preferentemente el flujo sanguíneo subendocárdico.
- El bloqueo del receptor B2 atenuó los efectos de la bradicinina en el flujo y la distribución.
- La inhibición de EDRF redujo el flujo total y bloqueó la redistribución subendocárdica.
Conclusiones:
- La bradicinina intracoronaria mejora la perfusión subendocárdica.
- Este efecto está mediado por la estimulación del receptor B2 y la liberación de EDRF, posiblemente óxido nítrico.
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