Slow-wave sleep induced in cats by extremely small amounts of synthetic and pineal vasotocin injected into the third ventricle of the brain.
A single injection of 10(-6) pg synthetic arginine vasotocin (AVT), corresponding to about 600 molecules AVT, into the third ventricle of unanesthetized cats, induced slow-wave sleep 5 min after the injection. An equivalent amount, of a partially purified pineal AVT injected into the third ventricle, produced the same effects. After incubation with trypsin, pineal AVT completely lost its ability to induce slow-wave sleep. The slow-wave sleep induced by 10(-6) pg synthetic AVT injected intraventricularly could be matched by 1 microgram synthetic AVT injected intraperitoneally. Neither synthetic arginine vasopressin, nor synthetic oxytocin, injected intraventricularly in the amount of 10(-6) pg, was able to induce slow-wave sleep. Whereas in the control animals injected with pineal AVT after incubation with trypsin, or in the control animals injected with vasopressin or oxytocin, the paradoxical sleep averaged 21.9--22.8% of the sleep time, during a total recording time of 5 hr, in the cats injected with synthetic or pineal AVT, the paradoxical sleep was completely suppressed.
D000818:Animals; D002415:Cats; D002552:Cerebral Ventricles; D004305:Dose-Response Relationship, Drug; D006728:Hormones / Q000494:pharmacology*; D008297:Male; D008550:Melatonin / Q000494:pharmacology; D012890:Sleep / Q000187:drug effects*; D013329:Structure-Activity Relationship; D014668:Vasotocin / Q000008:administration & dosage / Q000494:pharmacology*
D006728:Hormones; D008550:Melatonin; D014668:Vasotocin