, Volume 109, Issue 4, pp 415–421 | Cite as

Differential effects of serotonergic and catecholaminergic drugs on ingestive behavior

  • Karen E. Asin
  • John D. Davis
  • Lisa Bednarz
Original Investigations


The serotonergic agonists fenfluramine and fluoxetine and the catecholaminergic agonists amphetamine and phenylpropanolamine are well known to cause a reduction in intake in rats. In the studies reported here we investigated the effects of these drugs on the microstructure of licking behavior of the rat ingesting 0.4 M sucrose. The purpose was to examine the similarities in the behavioral effects within and between these two classes of anorectic agents. The serotonergic agonists fenfluramine and fluoxetine caused a reduction in intake primarily by reducing the size of bursts and clusters of licking within the test meal without affecting the duration of the meal, suggesting a reduction in the palatability of the test solution. The catecholamine agonists amphetamine and phenylpropanolamine reduced intake primarily by reducing the number of bursts and clusters without affecting their size, suggesting a fractionation in the organization of the normal pattern of ingestion. The differences between the two serotonin and the two catecholamine agonists on the microstructure of the licking behavior suggest a different effect of the two neurotransmitters on the motor system that controls ingestive behavior. The similarities between the two different agonists within each class suggests a common neurotransmitter mechanism responsible for these two different effects on the behavior of the animals.

Key words

Anorectics Ingestion rate Microstructure of ingestion Food intake Sugars Carbohydrate Amphetamine Fenfluramine Fluoxetine Phenylpropanolamine Serotonin Norepinephrine 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Antelman SM, Rowland N, Kocan C (1981) Lack of cross tolerance among serotonergic drugs and sensitization of amphetamine's effect. In: Garattini S, Samanin R (eds) Anorectic agents: mechanisms of action and tolerance. Raven Press, New York, pp 45–62Google Scholar
  2. Blundell JE (1987) Structure, process, and mechanism: case studies in the psychopharmacology of feeding. In: Iverson LL, Iverson SD, Snyder SH (eds) Handbook of psychopharmacology. Plenum Press, New YorkGoogle Scholar
  3. Blundell JE, Latham CJ (1978) Pharmacological manipulation of feeding behavior: possible influences of serotonin and dopamine on food intake. In: Garattini S, Samanin R (eds) Central mechanisms of anorectic drugs. Raven Press, New York, pp 83–109Google Scholar
  4. Blundell JE, Latham CJ, Leshem MB (1976) Differences between the anorexic actions of amphetamine and fenfluramine — possible effects on hunger and satiety. J Pharmacol Psychopharmacol 28:471–477Google Scholar
  5. Burton MJ, Cooper SJ, Popplewell DA (1981) The effect of fenfluramine on the microstructure of feeding and drinking in the rat. Br J Pharmacol 72:621–633Google Scholar
  6. Carruba MO, Ricciardi S, Spano P, Mantegazza P (1985) Dopaminergic and serotonergic anorectics differentially antagonize insulin- and 2DG-induced hyperphagia. Life Sci 36:1739–1749Google Scholar
  7. Davis JD (1989) The microstructure of ingestive behavior. Ann My Acad Sci 575:106–121Google Scholar
  8. Davis JD (1990) Quick Lick [Computer program] Available from DiLog Instruments, 3124 Ortega Dr. Tallahassee, FL, 32312Google Scholar
  9. Davis JD, Levine M (1977) A model for the control of ingestion. Psychol Rev 89:379–412Google Scholar
  10. Davis JD, Smith GP (1992) Analysis of microstructure of the rhythmic tongue movements of rats ingesting maltose and sucrose solutions. Behav Neurosci 106:217–228Google Scholar
  11. Eisenberg MS, Maher TJ, Silverman HI (1987) A comparison of the effects of phenylpropanolamine,d-amphetamine andd-norpseudoephedrine on open-field locomotion and food intake in the rat. Appetite 9:31–37Google Scholar
  12. Fuller RW, Wong DT (1989) Fluoxetine: a serotonergic appetite suppressant drug. Drug Dev Res 17:1–15Google Scholar
  13. Goudie AJ, Thornton EW, Wheeler TJ (1976) Effect of Lilly 110140, a specific inhibitor of 5-hydroxytryptophan uptake, on food intake and on 5-hydroxytryptophan-induced anorexia. J Pharm Pharmacol 28:318–320Google Scholar
  14. Grill HJ, Norgren R (1978) Taste reactivity test: I. Mimetic responses to gustatory stimuli in neurological normal rats. Brain Res 143:263–279Google Scholar
  15. Henderson R (1990) Contact 104/108 Lickometer, Di Log Instruments & Systems, 3124 Ortega Dr. Tallahassee, FL, 32312Google Scholar
  16. Hsiao S, Spencer R (1983) Analysis of the licking response in rats: Effects of cholecystokinin and bombesin. Behav Neurosci 91:234–245Google Scholar
  17. Knowler WC, Ukena ET (1973) The effect of chlorpromazine, pentobarbital, chlordiazepoxide andd-amphetamine on rates of licking in the rat. J Pharmacol Exp Ther 184:385–397Google Scholar
  18. Montgomery MJ, Burton MJ (1986) Effects of peripheral 5-HT on consumption of flavored solutions. Psychopharmacology 88:262–266Google Scholar
  19. Montgomery AMJ, Willner P (1988) Fenfluramine disrupts the behavioral satiety sequence in rats. Psychopharmacology 94:397–401Google Scholar
  20. Neil JC, Cooper SJ (1989) Effects of 5-hydroxytryptamine andd-fenfluramine on sham feeding and sham drinking in the gastric fistulated rat. Physiol Behav 46:949–953Google Scholar
  21. Pinder RM, Brogden RN, Sawyer PR, Speight TM, Avery GS (1975) Fenfluramine: a review of its pharmacological properties and therapeutic effects in obesity. Drugs 10:241–323Google Scholar
  22. Schneider LH, Davis JD, Watson CA, Smith GP (1990) Similar effect of raclopride and reduced sucrose concentration on the microstructure of sucrose sham feeding. Eur J Pharmacol 186:61–70Google Scholar
  23. Wellman PJ (1990) A review of the physiological bases of the anorectic action of phenylpropanolamine (d, 1-norephedrine). Neurosci Biobehav Rev 14:339–355Google Scholar
  24. Wellman PJ, Cockroft R (1986) Effects of amphetamine and phenylpropanolamine on latency to feed and cumulative liquid diet intake in rats. Pharmacol Biochem Behav 32:147–150Google Scholar
  25. Wiesenfeld ZB, Halperin P, Tapper DN (1977) Licking behavior: evidence of a hypoglossal oscillator. Science 196:1122–1124Google Scholar
  26. Wilkinson L (1990) SYSTAT 5.0, The system for statistics [Computer program]. Systat Evanston ILGoogle Scholar
  27. Willner P, McGuirk J, Phillips G, Muscat R (1990) Behavioural analysis of the anorectic effect of fluoxetine and fenfluramine Psychopharmacology 102:273–277Google Scholar

Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • Karen E. Asin
    • 1
  • John D. Davis
    • 2
  • Lisa Bednarz
    • 1
  1. 1.Abbott Laboratories, Neuroscience Research DivisionPharmaceutical Discovery, Department 47HAbbott ParkUSA
  2. 2.Department of PsychologyUniversity of Illinois, ChicagoChicagoUSA

Personalised recommendations