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La hibernación en osos negros: independencia de la supresión metabólica de la temperatura corporal
Øivind Tøien1, John Blake, Dale M Edgar
1Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA. otoien@alaska.edu
Science (New York, N.Y.)
|February 19, 2011
Resumen
Los osos negros reducen significativamente el metabolismo durante la hibernación, independientemente de la temperatura corporal. Esta supresión metabólica persiste durante semanas después de emerger de la densidad.
Área de la Ciencia:
- Fisiología Fisiología Fisiología.
- Zoología Zoología Zoología.
- Hibernación Biología de la hibernación.
Sus antecedentes:
- Los osos negros hibernan durante 5-7 meses al año, dejando de comer, beber y eliminar los desechos.
- Comprender los mecanismos fisiológicos de la hibernación es crucial para comprender la regulación metabólica.
Objetivo del estudio:
- Para investigar la tasa metabólica y la regulación de la temperatura corporal en osos negros en hibernación.
- Para determinar la relación entre la temperatura corporal y la supresión metabólica durante la hibernación.
Principales métodos:
- Monitoreo continuo de la tasa metabólica y la temperatura corporal en osos negros en hibernación.
- Análisis de los patrones del ritmo cardíaco y las respuestas fisiológicas durante los ciclos de hibernación.
Principales resultados:
- La tasa metabólica fue suprimida al 25% de los niveles basales.
- La temperatura corporal fue regulada cíclicamente entre 30°C y 36°C.
- La frecuencia cardíaca disminuyó significativamente, y se observó una arritmia sinusal profunda.
Conclusiones:
- Los osos negros en hibernación exhiben una supresión metabólica sustancial independiente de la disminución de la temperatura corporal.
- Se observó una recuperación tardía de la tasa metabólica hasta 3 semanas después de la hibernación.
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