Short communication The antipsychotic aripiprazole is a potent, partial agonist at the human 5-HT 1A receptor

Aripiprazole, 7-{4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butyloxy}-3,4-dihydro-2(1H)-quinolinone, a novel antipsychotic with partial agonist activity at dopamine D2 receptors, bound with high affinity to recombinant human 5-HT1A receptors (h5-HT1A) in Chinese hamster ovary cell membranes and displayed potent, partial agonism at 5-HT1A receptors in a guanosine-5VO-(3-[ 35 S]thio)-triphosphate ([ 35 S]GTPgS)-binding assay that was blocked completely by a selective 5-HT1A receptor antagonist. An interaction with 5-HT1A receptors may contribute to the overall efficacy of aripiprazole against symptoms of schizophrenia, including anxiety, depression, cognitive and negative symptoms, and to its favorable side-effect profile. Combined with previous studies demonstrating the potent partial agonism of aripiprazole at dopamine D2 receptors, this study suggests aripiprazole is the first dopamine–serotonin system stabilizer. D 2002 Elsevier Science B.V All rights reserved.