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Oscilación antifásica de los núcleos supraquiasmáticos izquierdo y derecho
H O de la Iglesia1, J Meyer, A Carpino
1Department of Neurology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA. hacho@bio.umass.edu
Science (New York, N.Y.)
|October 29, 2000
Resumen
La división del ritmo circadiano en los hámsters, donde la actividad se separa en dos episodios diarios, es causada por los dos osciladores de núcleos supraquiasmáticos (SCN) emparejados del cerebro que funcionan de manera independiente.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Cronobiología cronobiología.
- Comportamiento animal Comportamiento animal.
Sus antecedentes:
- Los ritmos circadianos gobiernan los ciclos biológicos diarios.
- La división del ritmo es un fenómeno inusual en el que la actividad se disocia en dos episodios diarios.
- Se supone que esta división es el resultado de dos osciladores circadianos antifase.
Objetivo del estudio:
- Para investigar la causa subyacente de la división del ritmo en los hámsters.
- Para determinar si los dos hemisferios del núcleo supraquiasmático (SCN) actúan como osciladores independientes.
Principales métodos:
- Análisis del comportamiento de la rueda en movimiento en hámsters que exhiben división del ritmo.
- Análisis de la expresión génica en el SCN izquierdo y derecho de hámsters divididos bajo condiciones de luz constante.
Principales resultados:
- Los hámsters divididos por comportamiento mostraron patrones de expresión génica distintos entre el SCN izquierdo y derecho.
- Estas diferencias de expresión génica lateralizada indican un funcionamiento independiente de los hemisferios del SCN.
Conclusiones:
- Los dos osciladores responsables de la división del ritmo se encuentran en el SCN izquierdo y derecho.
- Este hallazgo aclara la base neuronal de la división del ritmo circadiano en los mamíferos.
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