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El aumento de la endotelina-1 en la insuficiencia cardíaca y la pérdida de la respuesta normal al cambio postural
D J Stewart1, P Cernacek, K B Costello
1McGill Unit for the Prevention of Cardiovascular Disease, McGill University Department of Medicine, Royal Victoria Hospital, Montreal, Quebec, Canada.
Circulation
|February 1, 1992
Resumen
La endotelina-1 juega un papel en la compensación neurohumoral para el estrés hemodinámico. En sujetos normales, la endotelina-1 en plasma aumentó con la inclinación vertical, a diferencia de los pacientes con insuficiencia cardíaca.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Endocrinología Endocrinología.
- Nefrología Nefrología.
Sus antecedentes:
- Endothelin-1 es un potente péptido vasoconstrictor derivado del endotelio.
- Su papel en la compensación neurohumoral para el estrés hemodinámico no se entiende completamente.
Objetivo del estudio:
- Para investigar la contribución de la endotelina-1 a la compensación neurohumoral.
- Para comparar los niveles de endotelina-1 en sujetos normales y pacientes con insuficiencia cardíaca congestiva grave durante los cambios posturales.
Principales métodos:
- Se midieron los niveles plasmáticos de endotelina-1 mediante radioinmunoensayo en nueve voluntarios normales y seis pacientes con insuficiencia cardíaca.
- Se obtuvieron muestras de sangre en reposo y durante 30 minutos de inclinación vertical de 60 grados.
- Comparó las respuestas de endotelina-1 con otras mediadoras neurohumorales.
Principales resultados:
- Los sujetos normales mostraron un aumento bifásico en la endotelina-1 en plasma durante la inclinación vertical, similar a la dopamina.
- Los pacientes con insuficiencia cardíaca tenían niveles basales de endotelina-1 significativamente más altos y respuestas embotadas a la inclinación.
- Los patrones de respuesta de la endotelina-1 reflejaron los de otros mediadores de vasoconstricción.
Conclusiones:
- Las alteraciones plasmáticas de la endotelina-1 en la insuficiencia cardíaca y durante los cambios posturales se asemejan a otros mediadores de compensación neurohumoral.
- El aumento temprano de la endotelina-1 durante la inclinación sugiere su papel en la compensación del estrés hemodinámico.
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