Direct enhancement of hippocampal dopamine or serotonin levels as a pharmacodynamic measure of combined antidepressant - anticonvulsant action

Ilse Julia Smolders, Ralph Clinckers, Alfred Meurs, Dimitri De Bundel, Jeanelle Portelli, Guy Ebinger, Yvette Michotte

Research output: Contribution to journalArticlepeer-review

74 Citations (Scopus)

Abstract

The neurobiological relationships between epilepsy and depression are receiving increased experimental attention. A key role for limbic monoamines in depression has been established and we recently showed the importance of hippocampal monoamines in limbic seizure control. We here studied whether anticonvulsant compounds are antidepressant and can elevate hippocampal dopamine (DA) or serotonin (5-HT) levels determined by in vivo microdialysis in rats. We used assessment of seizure severity in the focal pilocarpine model, andidepressant-like activity within the rat forced swim and the mouse tail suspension tetst, and locomotor activity in an open field as behavioural tests. We studied the tricyclic antidepressant imipramine, the selective 5-HT reuptake inhibitor citalopram and the selective DA reuptake blocker GBR-12909. These compounds with combined antidepressant-anticonvulsant properties all directly enhanced extracellular hippocampal DA or 5-HT levels. Since glutamate-mediated hyperexcitability in temporal lobe regions seems to be involved in disturbed emotional behaviour, we next investigated possible antidepressant effects and hippocampal DA or 5-HT modulations exerted by selective ionotropic and metabotropic glutamate receptor ligands with anticonvulsant properties. Combined anticonvulsant - antidepressant activities of the NMDA antagonist MK-801 and the mGluR group I antagonists (AIDA, MPEP) were also associated with locally elicited increases in hippocampal DA and/or 5-HT levels. This study highlights that the hippocampus is an important site of action of combined anticonvulsant-antidepressant and monoamine enhancing effects.
Original languageEnglish
Pages (from-to)1017-1028
JournalNeuropharmacology
Volume54
Publication statusPublished - 2008

Keywords

  • Glutamate, Dopamine, Serotonin, Epilepsy

Fingerprint

Dive into the research topics of 'Direct enhancement of hippocampal dopamine or serotonin levels as a pharmacodynamic measure of combined antidepressant - anticonvulsant action'. Together they form a unique fingerprint.

Cite this