Abstract
Five cats were prepared with chronically implanted electrodes for recording sleep-wakefulness patterns. Four of these animals received fenfluramine at each of three dose levels and data was recorded for the following 12 hours. Percent of time in paradoxical sleep was significantly reduced by 2.5 and 7.5 mg/kg, but not by 0.5 mg/kg, of fenfluramine. The higher doses also increased slow-wave sleep and, at 7.5 mg/kg (an anorexigenic dose), total sleep time was significantly increased. Under similar conditions amphetamine, at an anorexigenic dose of 1 mg/kg, significantly suppressed both paradoxical sleep and slow-wave sleep in three cats.
Rebound of paradoxical sleep after suppression induced by 2.5 mg/kg of fenfluramine was not seen in either of two cats studied when sleep patterns were recorded for 48 hours. After 7.5 mg/kg of the drug, however, rebound was seen on days 3 and 4 after suppression of paradoxical sleep which lasted for over 26 hours. In two animals, daily administration of 2.5 mg/kg of fenfluramine for 16 consecutive days, followed by saline administration for three days, indicated that tolerance was developing to the suppression of paradoxical sleep produced by the drug.
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References
Baxter, B. L., Gluckman, M. I.: Iprindole: an antidepressant which does not block REM sleep. Nature (Lond.) 223, 750–752 (1969).
Duhalt, J., Verdavainne, C.: Modification of the cerebral serotonin level in the rat by 2-trifluoromethylphenyl-aminopropanes (Fenfluramine 768-S). Arch. int. Pharmacodyn. 170, 276–283 (1967).
Foxwell, M. H., Funderburk, W. H., Ward, J. W.: Studies on the site of action of a new anorectio agent, fenfluramine. J. Pharmacol. exp. Ther. 165, 60–70 (1969).
Hartman, E.: The 90-minute sleep-dream cycle. Arch. gen. Psychiat. 18, 280–286 (1968).
Hishikawa, Y., Nakai, K., Ida, H., Kaneko, Z.: The effect of imipramine, desmethylimipramine and chlorpromazine on the sleep-wakefulness cycle of the cat. Electroenceph. clin. Neurophysiol. 19, 518–521 (1965).
Hoffman, J. S., Domino, E. F.: Comparative effects of reserpine on the sleep cycle of man and cat. J. Pharmacol. exp. Ther. 170, 190–198 (1969).
Jovet, M.: Biogenic amines and the states of sleep. Science 163, 32–41 (1969).
Mayer, S. R., Southgate, P. J., Wilson, A. B.: Central nervous system stimulant action of fenfluramine in rabbits. J. Pharm. Pharmacol. 22, 239–240 (1970).
Opitz, K.: Anorexigene Phenylalkylamine und Serotoninstoffwechsel. Naunyn-Schmiedebergs Arch. Pharmak. exp. Path. 259, 56–65 (1967).
Oswald, I.: Drugs and sleep. Pharmacol. Rev. 20, 273–303 (1968).
-Jones, H. S., Mannerheim, J. E.: Effects of two slimming drugs on sleep. Brit. med. J. 1968 I, 796–799.
Rechtschaffen, A., Maron, L.: The effect of amphetamine on the sleep cycle. Electroenceph. clin. Neurophysiol. 16, 438–445 (1964).
Riley, I. D., Corson, J. C., Haider, I., Oswald, I.: Fenfluramine overdosage: clinical and EEG features. Lancet 1966 I, 1162–1163.
Ruckart, R.: Unpublished observations (1970).
Sterman, M. B., Knauss, T., Lehmann, D., Clemente, C. D.: Circadian sleep and waking patterns in the laboratory cat. Electroenceph. clin. Neurophysiol. 19, 509–517 (1965).
Wallach, M. B., Winters, W. D., Mandell, A. J., Spooner, C. E.: Effects of antidepressant drugs on wakefulness and sleep in the cat. Electroenceph. clin. Neurophysiol. 27, 574–580 (1969).
Yelnosky, J., Lawlor, R. B.: A comparative study of the pharmacologic actions of amphetamine and fenfluramine. Arch. int. Pharmacodyn. 184, 374–388 (1970).
Ziance, R., Buckley, J. P.: Some behavioral and biochemical effects of fenfluramine HCl on the central nervous system. Pharmacologist 11, 264 (1969).
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Johnson, D.N., Funderburk, W.H. & Ward, J.W. Effects of fenfluramine on sleep-wakefulness in cats. Psychopharmacologia 20, 1–9 (1971). https://doi.org/10.1007/BF00404052
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DOI: https://doi.org/10.1007/BF00404052