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Tipo de fibra muscular y ronquido habitual
S Smirne1, S Iannaccone, L Ferini-Strambi
1Sleep Disorders Centre, State University and Scientific Institute, Milan, Italy.
Lancet (London, England)
|March 9, 1991
Resumen
El ronquido habitual, un signo temprano de apnea obstructiva del sueño (AOS), está relacionado con tipos anormales de fibras musculares en las vías respiratorias superiores. Específicamente, los roncadores habituales muestran una estructura alterada del músculo constrictor faríngeo medio (MPCM), lo que sugiere un papel para la desregulación del tono muscular en la AOS.
Área de la Ciencia:
- Fisiología Fisiología Fisiología.
- Medicina del sueño Medicina del sueño.
- Biología Muscular Biología Muscular
Sus antecedentes:
- La apnea obstructiva del sueño (AOS) se asocia con anomalías anatómicas de las vías respiratorias superiores.
- La desregulación del tono muscular también está implicada en la patogénesis de la AOS.
- El ronquido habitual se considera una etapa inicial de la AOS.
Objetivo del estudio:
- Para investigar las características estructurales del músculo constrictor faríngeo medio (MPCM) en roncadores habituales en comparación con los no roncadores.
- Explorar posibles mecanismos basados en los músculos que contribuyen al ronquido habitual y la SAO.
Principales métodos:
- Análisis histológico de los tipos de fibra MPCM (I, IIa, IIb) de 13 hombres adultos (4 roncadores habituales, 9 no roncadores).
- Comparación de la distribución y el diámetro de las fibras MPCM entre roncadores y no roncadores.
- Evaluación de los cambios miopáticos o neurogénicos.
Principales resultados:
- El MPCM en no roncadores mostró diámetros de fibra más pequeños que los músculos típicos de las extremidades, con una mayor proporción de fibras de tipo I y IIa y menos fibras de tipo IIb.
- Los roncadores habituales exhibieron una distribución de fibras MPCM significativamente anormal (bajo tipo I y IIb, alto tipo IIa) en comparación con los no roncadores (p < 0.001).
- Las fibras de tipo IIa en roncadores habituales eran hipertróficas, sin evidencia de enfermedad miopática o neurogénica.
Conclusiones:
- El ronquido habitual se asocia con alteraciones específicas en la distribución del tipo de fibra del músculo de las vías respiratorias superiores (MPCM) y la hipertrofia.
- Estos hallazgos sugieren un papel potencial para la desregulación del tono muscular y los cambios adaptativos en la actividad de las neuronas motoras en el desarrollo del ronquido habitual y el SAO.
- Se necesita más investigación para dilucidar los mecanismos precisos que vinculan la función de las neuronas motoras a las adaptaciones MPCM en los roncadores.
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