Abstract
Homeostatic mechanism of sleep is thought to have an essential role for rest and maintenance of neural function. Recent report has suggested that vitamin A (retinol and its derivatives) is involved in the electroencephalogram (EEG) delta oscillation during sleep. However, the evidence is not confirmed by other study. In this study, we attempted to record sleep EEG and behavior, and to quantify striatal monoamines for mice that fed vitamin A deficient (VAD) diet during four weeks, in order to clarify the linkage between delta oscillation and vitamin A. VAD mice demonstrated a significant decrease of delta power in EEG and spontaneous activity throughout 24-hour. And then, striatal dihydroxyphenylacetic acid, which is a metabolite of dopamine, was significantly decreased in VAD mice. Our results suggest that deficiency of vitamin A induces the attenuation of spontaneous activity and dopaminergic dysfunction. This decrease of spontaneous activity is considered to suppress the delta power in homeostatic manner, because 6-hour forced awaking caused the recovery of delta power in VAD mice up to that in the control. [J Physiol Sci. 2007;57 Suppl:S137]
