Effect of GABAergic ligands on the anxiolytic-like activity of DOI -a 5-HT2A and 2C agonist- in the four-plate test in mice-

Authors
F. Massé, M. Hascoët, M. Bourin.

Lab
Faculté de Médecine, EA 3256 « Neurobiologie de l'anxiété et de la dépression », Nantes, France.

Journal
European Neuropsychopharmacology

Abstract
5-HTergic and GABAergic systems are involved in neurobiology of anxiety. Precedent studies have demonstrated that SSRIs possessed an anxiolytic-like effect in the four-plate test (FPT) at doses that did not modify spontaneous locomotor activity. This effect seems to be mediated through the activation of 5-HT2A postsynaptic receptors. The purpose of the present study was to examine the implication of GABA system in the anxiolytic-like activity of DOI in the FPT. To achieve this, the co-administration of DOI (5-HT2A/2C receptor agonists) with GABAA and GABAB receptor ligands was evaluated in the FPT. Alprazolam, diazepam and muscimol (for higher dose) potentiated the anxiolytic-like effect of DOI. Bicuculline, picrotoxin and baclofen inhibited the anxiolytic-like effect of DOI. Flumazenil and CGP 35348 had no effect on the anxiolytic-like activity of DOI. These results suggest that the GABA system seems to be strongly implicated in the anxiolytic-like activity of DOI in the FPT.

BIOSEB Instruments Used:
Aron Test or Four Plates Test (LE830)