Article

Óxido Nítrico: estudios sobre su papel como mediador en diversas funciones fisiológicas y fisiopatológicas

Vitae: Academia Biomédica Digital, ISSN 1317-987X, Nº. 16, 200357 pags 01/2003;
Source: OAI

ABSTRACT El óxido nítrico (NO) es una molécula única, con las características de neurotransmisor y con múltiples funciones en el organismo. Se sintetiza a partir de la L-arginina, originándose adicionalmente una molécula de L-citrulina, mediante una reacción catalizada por la sintasa del NO (NOS), de la cual se conocen 3 isoformas: dos constitutivas (cNOS) y una inducible (iNOS). La producción de iNOS es regulada transcripcionalmente: mientras que la forma cNOS es regulada en relación con su actividad. Por su naturaleza gaseosa, el NO difunde rápidamente (no se almacena); su vida media es extremadamente corta, por lo cual su cuantificación directa es difícil. El NO media efectos fisiológicos cuando es producido en bajas cantidades. Sin embargo, también está involucrado en actividades de citotoxicidad, cuando se genera en grandes cantidades. Estos aspectos son revisados y discutidos en el presente artículo, junto con el aporte original de nuestro grupo. Se incluyen estudios del NO y su papel fisiológico en la regulación de la presión arterial, en la diabetes mellitus tipo1 y en el ejercicio físico enpacientes.También se discute su rol en la fisiopatología de la inflamación neurogénica inducida por citotóxicos, en animales de experimentación.

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