発症前後のナルコレプシーモデルマウスにおける睡眠覚醒変化とカタプレキシー様行動の非侵襲的解析

摘要

Sleep and behavioral monitoring of young mice is necessary forunderstating the progress of these symptoms in congenital and acquireddiseases associated with sleep and movement disorders. In the current study,we have developed a non-invasive sleep monitoring system that identifies wakeand sleep of newborn mice using a simple piezoelectric transducer (PZT). Usingthis system, we have succeeded to detect age-dependent occurrences andchanges in sleep fragmentation of orexin/ataxin-3 narcoleptic mice (anarcoleptic mouse of model of postnatal hypocretin/orexin cell death) across thedisease onset. We also detected REM sleep/cataplexy patterns (i.e., immobilitywith clear heart bests [IMHB] signals due to the flaccid posture) by the PZTsystem, and found that sudden onset of REM sleep-like episodes specificallyoccur in narcoleptic, but not in wild type mice, suggesting that these episodesare likely to be cataplexy. In contrast, gradual onset of IMHB likely to reflectoccurrence of REM sleep.In summary, we have shown that the PZT system is useful as a noninvasivesleep and behavior monitoring system to analyze the developmentalaspects of sleep and movement disorders in mice models.