Tonic serotonergic control of ingestive behaviours in the pigeon (Columba livia): the role of the arcopallium

Behav Brain Res. 2009 Dec 28;205(2):396-405. doi: 10.1016/j.bbr.2009.07.017. Epub 2009 Jul 24.


This study examined the acute changes in feeding and drinking behaviours of free-feeding and free-drinking pigeons, in response to local injections of metergoline (MET, 5-HT(1/2) receptor antagonist; 7 and 20 nmol), GR46611 (GR, 5-HT(1B/1D) agonist; 2 and 6 nmol) or vehicle, into two components of the arcopallium: the nucleus taeniae of the amygdala (TnA) and the arcopallium intermedium (AI). In the TnA, the highest MET dose elicited a short-lived hyperphagy, without affecting drinking or non-ingestive behaviours during the first hour after injection. In contrast, all MET doses promptly increased drinking when injected in the AI, without affecting feeding; this effect was still evident 3 and 24 h after the treatment. When injected in the TnA, the highest GR dose promptly increased both food and water intake; these effects persisted 24 h after the treatments. GR injections in the AI evoked long-lasting increases in drinking, but not in feeding. Injections of these drugs into other arcopallial nuclei evoked no significant ingestive effects. These data indicate the presence of a tonic inhibitory influence of serotonergic inputs, partially mediated by 5-HT(1B/1D) receptors, on feeding- and drinking-related TnA circuits and on mechanisms controlling drinking in the AI. Compared to data from the rodent medial amygdala, our results suggest that a tonic inhibitory 5-HTergic control of feeding (but not drinking) behaviour, mediated by 5-HT(1/2) receptors and exerted in the medial amygdaloid area, may represent a broadly conserved functional attribute in the amniote brain, but probably involves many important taxa-specific neural mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acrylamides / administration & dosage
  • Acrylamides / pharmacology
  • Amygdala / drug effects
  • Amygdala / physiology*
  • Analysis of Variance
  • Animals
  • Brain / drug effects
  • Brain / physiology*
  • Catheterization
  • Columbidae
  • Dose-Response Relationship, Drug
  • Drinking / drug effects
  • Drinking / physiology*
  • Eating / drug effects
  • Eating / physiology*
  • Indoles / administration & dosage
  • Indoles / pharmacology
  • Male
  • Metergoline / administration & dosage
  • Metergoline / pharmacology
  • Receptor, Serotonin, 5-HT1B / metabolism
  • Receptor, Serotonin, 5-HT1D / metabolism
  • Receptors, Serotonin, 5-HT1 / metabolism*
  • Receptors, Serotonin, 5-HT2 / metabolism*
  • Serotonin 5-HT1 Receptor Agonists
  • Serotonin 5-HT1 Receptor Antagonists
  • Serotonin 5-HT2 Receptor Antagonists
  • Serotonin Antagonists / administration & dosage
  • Serotonin Antagonists / pharmacology
  • Serotonin Receptor Agonists / administration & dosage
  • Serotonin Receptor Agonists / pharmacology
  • Time Factors


  • Acrylamides
  • GR 46611
  • Indoles
  • Receptor, Serotonin, 5-HT1B
  • Receptor, Serotonin, 5-HT1D
  • Receptors, Serotonin, 5-HT1
  • Receptors, Serotonin, 5-HT2
  • Serotonin 5-HT1 Receptor Agonists
  • Serotonin 5-HT1 Receptor Antagonists
  • Serotonin 5-HT2 Receptor Antagonists
  • Serotonin Antagonists
  • Serotonin Receptor Agonists
  • Metergoline