[The role of opioid system in the regulation of the sleep-wakefulness cycle].

In chronic experiments influence of single administration of various doses of morphine (0.5, 2.0 and 3.0 mg/kg) on general behavior, structural organization of the sleep-waking cycle and some EEG and somato-vegetative parameters was studied in the cats. Intraperitoneal administration of morphine elicits numerous autonomic disorders, psychic derangement and complete deterioration of the sleep-waking cycle structure. The result certify that single administration of morphine induces activation of the opiate receptors in various structures of the brain, which entails deviations of behavioral and EEG parameters, activation of the structures responsible for initiation of behavioral waking, suppression of activity in those structure, which control the slow wave sleep triggering mechanisms, deterioration of the sleep quality and significant elevation of emotional tension against the baseline. On the basis of obtained data it is suggested that the opioid system plays an important role in the sleep-waking cycle regulatory mechanisms and other forms of brain integrative activity in general.