ABSTRACT
At each isolation step, hypnogenic and behavior-modulating activities of every fraction diluted 1:10 and 1:20 were tested under double-blind conditions. The amino acid sequence analysis specified the chemical structure of the hypnogenic factor as a novel nonapeptide with a molecular weight of 849. The hypnogenic effects were evaluated by comparing the amounts of wakefulness, and total sleep time, and sleep latencies between the saline-injected and the drug-injected rats during the 0-to 3-h, 3-to 6-h, and 0-to 6-h postinjection periods. In addition, the functional circulating of cerebrospinal fluid was verified by means of the drinking response to i.c.v. After observing the establishment of circadian rhythms in sleep-waking activity under the steady infusion of saline, the rats were subjected to the experimental treatments. Combining polygraphic records of locomotion, electroencephalography (EEG), delta EEG waves, and electromyographic, sleep-waking states were visually scored on a large-scale digitizer.
