Effects of modafinil and amphetamine on sleep-wake cycle after sleep deprivation in cats.

AIM The effects of modafinil and amphetamine on sleep-wake cycle and cortical power spectrum were assessed in the cats before and after sleep deprivation. METHODS The sleep deprivation in the cats was used with the water tank technique. Cats were administrated with modafinil (5 mg.kg-1 p.o.) or amphetamine (1 mg.kg-1) before and after sleep deprivation. RESULTS The waking effect of 8-10 h induced by modafinil before and after sleep deprivation was similar and was not followed by an increase in sleep rebound. On the contrary, the arousal effect about 8 h evoked by amphetamine after sleep deprivation was less lasting than that of 10-12 h observed in normal conditions and followed by an amplified rebound in both deep slow wave sleep and paradoxical sleep. CONCLUSION These results suggest the efficiency of modafinil against somnolence and hypersomnia without increasing subsequent sleep.