Hypnotic activity of melatonin: involvement of semicarbazide hydrochloride, blocker of synthetic enzyme for GABA.
Abstract
AIM: To assess the effect of semicarbazide hydrochloride (SCZ), the blocker of
synthetic enzyme for GABA, on the hypnotic activity of melatonin.
METHODS: Righting reflex method in mice and electroencephalography (EEG) in rats
were used to determine effects of SCZ on sleep and hypnotic activity of
melatonin.
RESULTS: Melatonin displayed a marked hypnotic activity both in righting reflex
experiment and EEG recording. SCZ had no influence on sleep parameters in mice
and rats when it was used alone. However, it blocked the sleep-potentiation
effect of melatonin in mice. SCZ also inhibited melatonin-induced increase in
total sleep time, slow wave sleep time, and paradoxical sleep time, and prevented
melatonin-induced decrease in awake time in rats.
CONCLUSION: SCZ antagonized the hypnotic activity of melatonin. It is thought
that the hypnotic activity of melatonin is mediated by GABAergic system.
Keywords:
synthetic enzyme for GABA, on the hypnotic activity of melatonin.
METHODS: Righting reflex method in mice and electroencephalography (EEG) in rats
were used to determine effects of SCZ on sleep and hypnotic activity of
melatonin.
RESULTS: Melatonin displayed a marked hypnotic activity both in righting reflex
experiment and EEG recording. SCZ had no influence on sleep parameters in mice
and rats when it was used alone. However, it blocked the sleep-potentiation
effect of melatonin in mice. SCZ also inhibited melatonin-induced increase in
total sleep time, slow wave sleep time, and paradoxical sleep time, and prevented
melatonin-induced decrease in awake time in rats.
CONCLUSION: SCZ antagonized the hypnotic activity of melatonin. It is thought
that the hypnotic activity of melatonin is mediated by GABAergic system.