Behavioral and neurochemical effects of 5-(4-[4-(5-Cyano-3-indolyl)-butyl)-butyl]-1-piperazinyl)-benzofuran-2-carboxamide (EMD 68843): a combined selective inhibitor of serotonin reuptake and 5-hydroxytryptamine(1A) receptor partial agonist.
5-(4-[4-(5-Cyano-3-indolyl)-butyl)-butyl]-1-piperazinyl)-benzofuran-2-carboxamide (EMD 68843; vilazodone) is a novel compound with combined high affinity and selectivity for the 5-hydroxytryptamine (5-HT) transporter and 5-HT(1A) receptors. EMD 68843 was tested as a prototype compound, which benefits from dual pharmacological effects that could increase extracellular 5-HT to levels higher than those produced by conventional selective serotonin reuptake inhibitors (SSRIs). In Sf9 cells, EMD 68843 increased guanosine 5'-O-(3-[(35)S]thiotriphosphate) binding to 69% of the magnitude of the full 5-HT(1A) receptor agonist R-(1)-trans-8-hydroxy-2-[N-n-propyl-N-(39-iodo-29-propenyl)] aminotetralin (8-OH-PIPAT), indicating that it is a partial agonist at 5-HT(1A) receptors. Acute, systemic administration of EMD 68843 produced a larger maximal increase of extracellular 5-HT than the SSRI fluoxetine in both the ventral hippocampus (HPv) (558 versus 274%) and the frontal cortex (FC) (527 versus 165%). Regional differences in the response to the two drugs were also observed. These effects may be attributed to the differential regulation of 5-HT release in the HPv and FC by 5-HT(1A) autoreceptors. When challenged with the 5-HT(1A) receptor agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), EMD 68843-induced increases in extracellular 5-HT were greatly reduced in the HPv but to a lesser extent in the FC. In behavioral studies, EMD 68843 produced antidepressant-like effects in the forced swimming test in both rats and mice but only within a narrow dosage range. Like fluoxetine, EMD 68843 did not produce the symptoms of the 5-HT behavioral syndrome in rats but, unlike fluoxetine, pretreatment with EMD 68843 blocked expression of the 5-HT behavioral syndrome induced by 8-OH-DPAT. Taken together, the results show that EMD 68843 augments extracellular 5-HT levels in forebrain regions to a greater extent than fluoxetine. At higher doses, however, weak efficacy of EMD 68843 at postsynaptic 5-HT(1A) receptors may inhibit the expression of rodent antidepressant-like behaviors.
Department of Psychiatry, University of Pennsylvania, 415 Curie Boulevard, Philadelphia, PA 19104-6140, USA.
Michelle E
ME
Page
John F
JF
Cryan
Arthur
A
Sullivan
Ashutosh
A
Dalvi
Berangere
B
Saucy
David R
DR
Manning
Irwin
I
Lucki
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects*; D001572:Benzofurans / Q000494:pharmacology*; D001923:Brain Chemistry / Q000187:drug effects*; D002460:Cell Line; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005473:Fluoxetine / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000378:metabolism; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D007211:Indoles / Q000494:pharmacology*; D017551:Microdialysis; D010879:Piperazines; D017397:Prefrontal Cortex / Q000187:drug effects / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D011985:Receptors, Serotonin / Q000187:drug effects*; D044263:Receptors, Serotonin, 5-HT1; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*; D013550:Swimming / Q000523:psychology; D000069503:Vilazodone Hydrochloride
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D018687:Antidepressive Agents, Second-Generation; D001572:Benzofurans; D005473:Fluoxetine; D019204:GTP-Binding Proteins; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D007211:Indoles; D010879:Piperazines; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D017366:Serotonin Receptor Agonists; D017367:Selective Serotonin Reuptake Inhibitors; D000069503:Vilazodone Hydrochloride