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Efecto de la activación plaquetaria en el flujo sanguíneo colateral coronario
1Division of Cardiology, Department of Internal Medicine, University of Minnesota Medical School, Minneapolis, Minn, USA.
Circulation
|October 7, 1998
Resumen
El factor de activación plaquetaria (PAF) reduce el flujo sanguíneo colateral coronario al causar vasoconstricción. Este efecto está mediado por el tromboxano A2, destacando su papel en la regulación del flujo sanguíneo a través de estos vasos vitales.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Biología plaquetaria Biología plaquetaria.
Sus antecedentes:
- Los productos plaquetarios como el tromboxano A2 y la serotonina estrechan los vasos colaterales coronarios.
- El papel del factor de activación plaquetaria (PAF, por sus siglas en inglés) en la disminución del flujo sanguíneo colateral coronario era previamente desconocido.
Objetivo del estudio:
- Investigar si la activación plaquetaria intravascular por el FAP puede disminuir el flujo sanguíneo colateral coronario.
Principales métodos:
- El crecimiento de los vasos colaterales coronarios fue inducido en perros adultos a través de la embolización LAD.
- El flujo sanguíneo colateral se midió por el flujo retrógrado de una arteria canulada.
- El factor de activación plaquetaria (PAF) se inyectó en la arteria coronaria principal izquierda.
Principales resultados:
- La inyección de FAP causó una disminución significativa en el flujo sanguíneo retrógrado, lo que indica vasoconstricción.
- La reducción máxima en el flujo sanguíneo fue del 40,3% y volvió a la normalidad en 15 minutos.
- El bloqueo del tromboxano A2 abolió la respuesta vasoconstrictora al PAF, desenmascarando un efecto vasodilatador.
Conclusiones:
- El factor de activación plaquetaria (PAF) induce la vasoconstricción, disminuyendo el flujo sanguíneo coronario colateral.
- El efecto vasoconstrictor del PAF en los vasos colaterales coronarios es dependiente del tromboxano A2.
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