Según un estudio experimental, mantener las luces encendidas de las UCI neonatales puede obstaculizar que los niños prematuros desarrollen adecuadamente su reloj biológico. Por el contrario, el ciclo normal de luz de 12 horas parece coordinar adecuadamente los mecanismos circadianos.
En este trabajo de la Universidad Vanderbilt de Nashville (Estados Unidos), publicado en “Pediatric Research”, emplearon ratones transgénicos que producían una fluorescencia verde por la acción de un gen regulado por el reloj biológico. Estudiaron a 10 madres y a sus hijos durante 20 días, 5 con luz constante y 5 con 12 horas de luz y 12 a oscuras. Tras el sacrificio de los animales, analizaron el núcleo supraquiasmático (NSQ) cerebral, donde se sitúa el centro del sistema del reloj interno, y observaron que las neuronas del NSQ de ratones expuestos a periodos cíclicos de luz se sincronizaban rápidamente, mientras que las de ratones en luz constante presentaban oscilaciones.
Pediatric Research 2006; 60:304-308
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