Effect of clomipramine on sleep and EEG power spectra in the diurnal rodent Eutamias sibiricus.

Sleep was recorded in the diurnal rodent Eutamias sibiricus, chronically implanted with EEG and EMG electrodes. The tricyclic antidepressant drug clomipramine suppressed the duration of REM sleep and EEG power density in the frequencies between 1.5 and 13.5 Hz in nonREM sleep. During the administration of clomipramine, 24 h of sleep deprivation by forced locomotion significantly reduced the duration of waking and increased the duration of nonREM sleep. During the first 2 h of recovery sleep, EEG power density of the frequencies between 2.5 and 6 Hz was enhanced. These effects of sleep deprivation were to a large extent similar to those of sleep deprivation under drug free conditions. It is concluded that clomipramine affects the EEG in nonREM sleep but does not interfere substantially with nonREM sleep regulatory processes, which are activated by sleep deprivation.