The benzodiazepine antagonist, Ro 15-1788, increases REM and slow wave sleep in the dog

The benzodiazepine antagonist, Ro 15-1788, increases REM and deep slow-wave in dogs at a dose of 10 mg/kg orally. These actions are opposite to that of diazepam. This suggests either that Ro 15-1788 possesses hitherto undescribed intrinsic partial inverse agonist activity or that it is antagonizing an endogenous benzodiazepine-like substance which is involved in modulating sleep-wakefulness.