Abstract: AIM: To investigate the effect of prostanoid DPreceptors ( DPR) on sleep-wake regulation in mice.METHODS: Under pentobarbital anesthesia,mice were chronically implanted with electroencephalogram( EEG) and electromyogram ( EMG) electrodes for polysomnographic recordings.The spontaneous sleep-wake cycles were monitored continuously by EEG/EMG recording system for 24 h beginning at 8 ∶; 00 P.m.and analyzed by SLEEPSIGN software in DPR knock out ( KO)and wild type (WT) mice.RESULTS: DPR-KO mice exhibited a similar circadian rhythm of sleep-wake cycles to WT mice.The amounts of rapid eye movement ( REM)sleePor non-REM ( NREM) sleePduring both the light and dark periods were identical between the DPR-KO and WT mice.Whereas, an increase in the episode number of wakefulness and a shortage in the duration of NREM sleePwere found in DPR-KO mice during the light period compared with WT mice.Moreover, DPR-KO mice showed lower activity in delta-wave component in NREM sleePand higher activity in theta-wave component in REM sleePthan WT mice.CONCLUSION: DPR plays a crucial role in mediating the prostaglandin D2-induced sleeP.Deficiency of DPR results in the low intensity and fragmented diurnal NREM sleePand the high vigilance REM sleep,with the normal circadian rhythm of sleePin mice.

Key words: prostaglandin D2, DPreceptor, sleepwake cycle, rapid eye movement sleep, non-rapid eye movement sleep, mice