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Nuevo índice de redistribución del flujo sanguíneo nutritivo al músculo esquelético durante el ejercicio dinámico
1Second Department of Internal Medicine, Toyama Medical and Pharmaceutical University, Japan.
Circulation
|April 1, 1992
Resumen
Este estudio introduce un método para cuantificar la redistribución del flujo sanguíneo en el ejercicio de las piernas utilizando la actividad del talio. La proporción de talio entre las piernas en ejercicio y en reposo indica efectivamente cambios en el tono vascular durante el ejercicio.
Área de la Ciencia:
- Fisiología del ejercicio Fisiología del ejercicio
- Fisiología cardiovascular fisiología cardiovascular.
- Medición de imágenes de la medicina nuclear.
Sus antecedentes:
- La redistribución de la salida cardíaca a los músculos de trabajo es crucial durante el ejercicio.
- Cuantificar la distribución del flujo sanguíneo a los grandes grupos musculares durante el ejercicio ergonómico o en la cinta de correr ha sido un desafío.
Objetivo del estudio:
- Desarrollar y validar un método para cuantificar la redistribución del flujo sanguíneo a los músculos de trabajo durante el ejercicio.
- Para evaluar los cambios regionales en la resistencia vascular y el flujo sanguíneo en las extremidades que hacen ejercicio.
Principales métodos:
- Utilizado talio-201 (Tl-201) scintigraphy para medir la radiactividad regional en el ejercicio y las piernas en reposo.
- Comparación de la actividad del talio en la pierna de pedaleo frente a la pierna de reposo contralateral en 10 sujetos sanos.
- Distribución del talio medida en reposo, umbral anaeróbico y pico de ejercicio durante el ciclismo con una sola pierna.
Principales resultados:
- La actividad del talio aumentó significativamente en el muslo y la pantorrilla en ejercicio en el umbral anaeróbico y el pico de ejercicio.
- Se observó una disminución significativa en la actividad del talio en los terneros que no hacían ejercicio.
- La proporción de actividad de talio entre las piernas que hacen ejercicio y las que no lo hacen aumentó sustancialmente, lo que refleja la redistribución del flujo sanguíneo.
Conclusiones:
- La redistribución del flujo sanguíneo ocurre principalmente durante el ejercicio leve a moderado.
- La relación de actividad del talio entre las piernas que hacen ejercicio y las que no lo hacen sirve como un índice cuantitativo no invasivo de las diferencias de tono vascular y la redistribución del flujo sanguíneo.
- Durante el ejercicio extenuante, el flujo sanguíneo en las piernas se ve influenciado principalmente por el aumento de la producción cardíaca.
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