Send to

Choose Destination
Physiol Behav. 2011 Sep 1;104(3):480-7. doi: 10.1016/j.physbeh.2011.05.011. Epub 2011 May 13.

Refeeding after a 24-hour fasting deepens NREM sleep in a time-dependent manner.

Author information

Department of Integrative Physiology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503, Japan.


Sleep/wake cycle is regulated by a variety of neuropeptides in the hypothalamus, a brain region that also regulates energy homeostasis and feeding behavior. Since circadian rhythms are affected by energy metabolism and feeding condition, we investigated whether changes in feeding regimen would influence sleep/wake parameters and body temperature. We monitored sleep and body temperature across three days of baseline (day 1), fasting (day 2), and refeeding (day 3) conditions under ordinary ambient temperature and employed different refeeding schedules. Refeeding at ZT1 following the 24-h fasting enhanced EEG delta power in NREM sleep. However, when the time of refeeding was set at either ZT7 or ZT12, the enhancement of EEG delta power was attenuated. The amount of NREM sleep was not largely affected by a 24-h fasting started at ZT1, although fasting that started at ZT12 changed the temporal distribution of NREM sleep. Hypothalamic nNOS mRNA level was increased both before and after refeeding at ZT1 compared with control condition, while there was no significant change in mice refed at ZT7. Level of NPY mRNA in the arcuate nucleus was increased before the refeeding only at ZT1. These results suggest that refeeding after a 24-h fasting makes NREM sleep deeper in a time-dependent manner.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center