Nicotine: effect on the sleep cycle of the cat.

Small doses of nicotine (0.005 to 0.01 milligram per kilogram of body weight) given intravenously to sleeping cats with indwelling brain electrodes produce (i) initial electroen-cephalographic activation which was accompanied by behavioral arousal; (ii) a few minutes later, slow-wave sleep; and (iii) within 15 to 30 minutes, fast-wave sleep. Although peripheral afferent stimulation, release of epinephrine, and arginine vasopressin contribute to the initial arousal effects, the primary action of nicotine appears to be on the central nervous system.