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Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
El óxido nítrico inhibe la respuesta inotrópica positiva a la estimulación beta-adrenérgica en humanos con disfunción
1Cardiomyopathy Center, Boston University School of Medicine, MA 02118, USA.
Circulation
|October 15, 1995
Resumen
El óxido nítrico (NO) en el corazón reduce la respuesta a la estimulación beta-adrenérgica en pacientes con disfunción ventricular izquierda (LV). La inhibición del NO mejora esta respuesta, lo que sugiere que el NO contribuye a la hiporresponsividad.
Área de la Ciencia:
- Cardiología Cardiología.
- Fisiología Fisiología Fisiología.
- Farmacología Farmacología.
Sus antecedentes:
- Se sabe que el óxido nítrico (NO) reduce la contractilidad cardíaca en respuesta a la estimulación beta-adrenérgica.
- Este efecto se ha observado en cultivos celulares y modelos animales.
Objetivo del estudio:
- Investigar si el óxido nítrico (NO) producido endógenamente en el corazón humano inhibe los efectos inotrópicos positivos de la estimulación beta-adrenérgica.
- Para probar esto en pacientes con disfunción ventricular izquierda (LV).
Principales métodos:
- Los pacientes con disfunción de LV recibieron infusiones de dobutamina (intracoronaria o periférica).
- El inhibidor de la sintasa de óxido nítrico, NG-monometil-L-arginina (L-NMMA), fue administrado por infusión intracoronaria.
- Se midió la presión ventricular izquierda y dP/dt para evaluar la contractilidad.
Principales resultados:
- La dobutamina intracoronaria aumentó el pico de LV +dP/dt en un 33%.
- La L-NMMA por sí sola no afectó la función cardíaca basal.
- La infusión concomitante de L-NMMA potenció el efecto de la dobutamina en +dP/dT en un 30-37%.
Conclusiones:
- El óxido nítrico (NO) derivado del corazón atenúa la respuesta inotrópica positiva a la estimulación beta-adrenérgica en humanos con disfunción de LV.
- NO puede desempeñar un papel en la respuesta reducida a los agentes beta-adrenérgicos observados en estos pacientes.
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