Circadian clock genes and sleep homeostasis.

摘要: Circadian and sleep-homeostatic processes both contribute to sleep timing structure. Elimination of circadian rhythms through lesions the suprachiasmatic nuclei (SCN), master pacemaker, leads fragmentation wakefulness but does not eliminate homeostatic response loss as indexed by increase in EEG delta power. In humans, power declines during episodes nearly independently phase. Such observations have contributed prevailing notion that are separate recent data imply this segregation may extend molecular level. Here we summarize criteria evidence for a role clock genes homeostasis. Studies mice with targeted disruption core revealed alterations rhythmicity well changes duration, structure Clock-gene expression brain areas outside SCN, particular cerebral cortex, depends large extent on prior sleep-wake history. Evidence effects homeostasis has also been obtained Drosophila pointing phylogenetically preserved pathway. These findings suggest that, while within SCN utilized set internal time-of-day, forebrain same feedback circuitry be track time spent awake asleep. The mechanisms which clock-gene is coupled distribution could cellular energy charge whereby act sensors. underscore interrelationships between metabolism, rhythmicity, regulation.