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Updated: Jul 11, 2026
08:25
Measuring Nitrite and Nitrate, Metabolites in the Nitric Oxide Pathway, in Biological Materials using the Chemiluminescence Method
Published on: December 25, 2016
La infusión de nitrito en humanos y primates no humanos: efectos endocrinos, farmacocinética y formación de
André Dejam1, Christian J Hunter, Carole Tremonti
1Molecular Medicine Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Circulation
|September 26, 2007
Resumen
El nitrito actúa como un potente vasodilatador y depósito de óxido nítrico (NO), regulando la función vascular y la homeostasis del NO. Este estudio revela el nitrito.
Área de la Ciencia:
- Fisiología cardiovascular fisiología cardiovascular.
- Endocrinología Endocrinología.
- Farmacología Farmacología.
Sus antecedentes:
- Se reconoce el papel del nitrito como vasodilatador y molécula de señalización en concentraciones fisiológicas.
- Se sugieren posibles contribuciones a la vasodilatación hipóxica y los efectos del nitrato.
- Sigue habiendo preguntas clave con respecto a la potencia, cinética, mecanismo y tolerancia del nitrito.
Objetivo del estudio:
- Para investigar la potencia, la cinética y el mecanismo de acción del nitrito como vasodilatador.
- Para determinar si el nitrito induce tolerancia, a diferencia de los nitratos orgánicos.
- Para aclarar el papel del nitrito en la homeostasis del óxido nítrico y la regulación vascular.
Principales métodos:
- Estudios bioquímicos, fisiológicos y farmacológicos en voluntarios humanos y primates no humanos.
- Se emplearon protocolos de infusión de nitrito.
- Los mecanismos probados incluyeron la reducción por xantina oxidorreductasa, la desproporción no enzimática y la reducción por desoxihemoglobina.
Principales resultados:
- El nitrito demostró una potente y rápida vasodilatación a concentraciones cercanas a las fisiológicas.
- El nitrito funciona como un depósito endocrino de óxido nítrico, causando la vasodilatación remota.
- El nitrito se reduce al óxido nítrico a través de reacciones intravasculares con la hemoglobina y el ascorbato.
- La inhibición de la xantina oxidorreductasa potencia, en lugar de inhibir, la vasodilatación inducida por el nitrito.
- El nitrito no indujo tolerancia, en contraste con los nitratos orgánicos.
Conclusiones:
- El nitrito sirve como un regulador fisiológico de la función vascular y la homeostasis endocrina del óxido nítrico.
- El nitrito es un metabolito activo de los nitratos orgánicos.
- El nitrito ofrece un potencial terapéutico para eludir la tolerancia enzimática asociada con los nitratos orgánicos.
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