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Sistema nervioso no adrenérgico, no colinérgico y calibre de vía aérea durante la noche en sujetos asmáticos y
T W Mackay1, M F Fitzpatrick, N J Douglas
1Department of Medicine, City Hospital, Edinburgh, UK.
Lancet (London, England)
|November 23, 1991
Resumen
Los síntomas de asma nocturna como tos y sibilancias pueden deberse a la reducción de la función nerviosa no adrenérgica, no colinérgica (NANC) en la mañana. Este estudio investigó las variaciones del sistema NANC, revelando un vínculo potencial con la broncoconstricción nocturna.
Área de la Ciencia:
- Medicina de las vías respiratorias.
- Neuroinmunología La neuroinmunología.
- Fisiología pulmonar Fisiología pulmonar
Sus antecedentes:
- Los síntomas nocturnos del asma, que incluyen tos y sibilancias, son comunes en pacientes asmáticos.
- El aumento del tono parasimpático por sí solo no explica por completo la broncoconstricción nocturna.
Objetivo del estudio:
- Para investigar la variación durante la noche en la función de la vía neuronal no adrenérgica, no colinérgica (NANC) que innerva el músculo liso bronquial.
- Para determinar si la inhibición del sistema NANC a primera hora de la mañana contribuye a la broncoconstricción nocturna.
Principales métodos:
- Se evaluó la función NANC comparando el efecto broncodilatador de la capsaicina (un estimulante NANC) a las 0400 h y a las 1600 h.
- Los sujetos incluyeron 12 individuos normales y 12 pacientes con asma leve, probados después del bloqueo parasimpático y beta-adrenérgico.
- El efecto broncodilatador se midió como el cambio en la resistencia oscilatoria (Ros); el diseño del estudio fue aleatorizado y doble ciego.
Principales resultados:
- La broncodilatación en respuesta a la capsaicina fue significativamente mayor a las 1600 h en comparación con las 0400 h tanto en sujetos normales como en pacientes asmáticos.
- Los sujetos normales mostraron una disminución del 9% en Ros a las 1600 h frente al -2% a las 0400 h (p < 0,001).
- Los pacientes asmáticos mostraron una disminución del 1% en Ros a las 1600 h frente al -7% a las 0400 h (p = 0,001).
Conclusiones:
- Los hallazgos sugieren que la función nerviosa NANC se reduce en la madrugada.
- Esta inhibición de la función NANC puede ser un factor que contribuye a la broncoconstricción nocturna observada en el asma.
- Una mayor investigación sobre la modulación del sistema NANC podría ofrecer nuevas estrategias terapéuticas para el control del asma nocturno.
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