Changes of sleep patterns in rats with chronic constriction injury under aversive conditions.

In the present study, we investigated the changes of sleep parameters in rats with chronic constriction injury (CCI) under aversive conditions. The electroencephalogram (EEG) in the frontal cortex of CCI rats and electromyogram (EMG) were measured over 6 h by placing rats on sandpaper as an aversive condition, to compare with rats placed on sawdust. Six days after CCI surgery, the rats exhibited significant mechanical allodynia, and also had neuropathic pain.

[Effect of santalol on the sleep-wake cycle in sleep-disturbed rats].

Sandalwood oil is widely used in aromatherapy for alleviating various symptoms. Santalol, a major component of sandalwood oil, has been reported to have central nervous system depressant effects such as sedation. In the present study, we investigated the effect of santalol on the sleep-wake cycle in sleep-disturbed rats.

Effect of tandospirone on sleep latency in rats placed on a grid suspended over water.

The present study was performed to examine the effect of tandospirone on sleep latency in a new insomnia animal model by placing rats on a grid suspended over water. For investigating the mechanism of tandospirone, the effect of tandospirone on sleep latency was also studied using rats that were depleted with neuronal serotonin (5-HT) after p-chlorophenylalanine administration. Tandospirone caused a shortening of sleep latency dose-dependently, and a significant effect was observed at 20 mg/kg, p.

Hypnotic activities of chamomile and passiflora extracts in sleep-disturbed rats.

In the present study, we investigated hypnotic activities of chamomile and passiflora extracts using sleep-disturbed model rats. A significant decrease in sleep latency was observed with chamomile extract at a dose of 300 mg/kg, while passiflora extract showed no effects on sleep latency even at a dose of 3000 mg/kg. No significant effects were observed with both herbal extracts on total times of wakefulness, non-rapid eye movement (non-REM) sleep and REM sleep.

Effects of kava-kava extract on the sleep-wake cycle in sleep-disturbed rats.

Rationale: Kava-kava extract may be useful as an herbal medicine for treatment of insomnia and anxiety.

Objectives: The present study was undertaken to investigate the effects of kava-kava extract on the sleep-wake cycle in comparison with that of flunitrazepam using sleep-disturbed rats.

Methods: Electrodes for measurement of electroencephalogram (EEG) and electromyogram (EMG) were implanted into the frontal cortex and the dorsal neck muscle of rats.

Effects of three hypnotics on the sleep-wakefulness cycle in sleep-disturbed rats.

Rationale: New sleep disturbance model in rats is useful for estimating the characteristics of some hypnotics.

Objectives: The present study was undertaken to investigate the utility of a sleep disturbance model by placing rats on a grid suspended over water using three kinds of hypnotics, that is, short-acting benzodiazepine (triazolam), intermediate-acting benzodiazepine (flunitrazepam) and long-acting barbiturate (phenobarbital).

Methods: Electrodes for measurement of EEG and EMG were implanted into the frontal cortex and the dorsal neck muscle of rats.