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Updated: Jul 14, 2026
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Non-invasive Assessment of Microvascular and Endothelial Function
Published on: January 29, 2013
Respuesta vascular de los miembros a la estimulación del receptor beta-adrenérgico en pacientes con insuficiencia
M A Creager1, R J Quigg, C J Ren
1Cardiovascular Division, Brigham and Women's Hospital, Boston, MA 02115.
Circulation
|June 1, 1991
Resumen
La desensibilización del receptor beta-adrenérgico no causa alteración de la vasodilatación de las extremidades en pacientes con insuficiencia cardíaca congestiva. Las respuestas al flujo sanguíneo de los miembros al isoproterenol y la nitroprussida de sodio se conservaron en pacientes con insuficiencia cardíaca.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Farmacología Farmacología.
Sus antecedentes:
- La insuficiencia cardíaca congestiva (ICF) se asocia con respuestas reducidas a los agonistas beta-adrenérgicos.
- El papel de la desensibilización periférica de los beta-adrenorreceptores en el deterioro de la vasodilatación de las extremidades en la insuficiencia cardiaca congestiva sigue sin estar claro.
Objetivo del estudio:
- Investigar si la desensibilización de los beta-adrenoceptores contribuye a la vasodilatación anormal de las extremidades en pacientes con insuficiencia cardíaca congestiva.
Principales métodos:
- Se administraron infusiones de isoproterenol (beta-agonista) y nitroprussida de sodio (vasodilatador) en la arteria intrabraquial a 13 pacientes con FCH y 14 controles sanos.
- El flujo sanguíneo en el antebrazo se midió utilizando la pletismografía de oclusión venosa.
- Se evaluó el potencial vasodilatador máximo durante la hiperemia reactiva.
Principales resultados:
- La respuesta máxima al flujo sanguíneo en el antebrazo al isoproterenol fue similar en pacientes con ECH y controles.
- Las relaciones dosis-respuesta para el isoproterenol y la nitroprussida de sodio se mantuvieron en pacientes con CHF.
- Los niveles elevados de norepinefrina en el plasma en pacientes con CHF no se correlacionaron con la respuesta al isoproterenol.
Conclusiones:
- La desensibilización de los receptores beta-adreno no es la causa del deterioro de la vasodilatación de las extremidades en pacientes con insuficiencia cardíaca congestiva.
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