title: The effect of serotonin(1A) receptor agonism on antipsychotic drug-induced dopamine release in rat striatum and nucleus accumbens.
abstract: Serotonin (5-HT)(1A) receptor agonism may be of interest in regard to both the antipsychotic action and extrapyramidal symptoms (EPS) of antipsychotic drugs (APD) based, in part, on the effect of 5-HT(1A) receptor stimulation on the release of dopamine (DA) in the nucleus accumbens (NAC) and striatum (STR), respectively. We investigated the effect of R(+)-8-hydroxy-2-(di-n-propylamino)-tetralin (R(+)-8-OH-DPAT) and n-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-n-(2-pyridinyl)cyclohe xanecarboxamide trihydrochloride (WAY100635), a selective 5-HT(1A) receptor agonist and antagonist, respectively, on basal and APD-induced DA release. In both STR and NAC, R(+)-8-OH-DPAT (0.2 mg/kg) decreased basal DA release; R(+)-8-OH-DPAT (0.05 mg/kg) inhibited DA release produced by the 5-HT(2A)/D(2) receptor antagonists clozapine (20 mg/kg), low dose risperidone (0.01 and 0. 03 mg/kg) and amperozide (10 mg/kg), but not that produced by high dose risperidone (0.1 and 1.0 mg/kg) or haloperidol (0.01-1.0 mg/kg), potent D(2) receptor antagonists. This R(+)-8-OH-DPAT-induced inhibition of the effects of clozapine, risperidone and amperozide was antagonized by WAY100635 (0.05 mg/kg). WAY100635 (0.1-0.5 mg/kg) alone increased DA release in the STR but not NAC. The selective 5-HT(2A) receptor antagonist M100907 (1 mg/kg) did not alter the effect of R(+)-8-OH-DPAT or WAY100635 alone on basal DA release in either region. These results suggest that 5-HT(1A) receptor stimulation inhibits basal and some APD-induced DA release in the STR and NAC, and that this effect is unlikely to be mediated by an interaction with 5-HT(2A) receptors. The significance of these results for EPS and antipsychotic action is discussed.
authors.affiliation: The First Floor Laboratory, Psychopharmacology Division, Department of Psychiatry, Vanderbilt University School of Medicine, 1601 23rd Avenue South, Suite 306, The Psychiatric Hospital at Vanderbilt, Nashville, TN 37212, USA. ichikaj@ctrvax.vanderbilt.edu
authors.forename: J
authors.initials: J
authors.lastname: Ichikawa
authors.forename: H Y
authors.initials: HY
authors.lastname: Meltzer
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology*; D003024:Clozapine / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D005464:Fluorobenzenes / Q000494:pharmacology; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D017551:Microdialysis; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D010879:Piperazines / Q000494:pharmacology*; D010880:Piperidines / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin / Q000502:physiology*; D044263:Receptors, Serotonin, 5-HT1; D018967:Risperidone / Q000494:pharmacology; D012701:Serotonin / Q000493:pharmacokinetics; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D014316:Tritium
chemical_list: D014150:Antipsychotic Agents; D005464:Fluorobenzenes; D010879:Piperazines; D010880:Piperidines; D011725:Pyridines; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; C049058:amperozide; D014316:Tritium; D012701:Serotonin; C090413:N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; C079049:volinanserin; D003024:Clozapine; D006220:Haloperidol; D018967:Risperidone; D004298:Dopamine