title: Atypical antipsychotic properties of blonanserin, a novel dopamine D2 and 5-HT2A antagonist.
abstract: Blonanserin is a novel antipsychotic agent that preferentially interacts with dopamine D(2) and 5-HT(2A) receptors. To assess the atypical properties of blonanserin, we evaluated its propensity to induce extrapyramidal side effects (EPS) and to enhance forebrain Fos expression in mice. The actions of AD-6048, a primary metabolite of blonanserin, in modulating haloperidol-induced EPS were also examined. Blonanserin (0.3-10mg/kg, p.o.) did not significantly alter the pole-descending behavior of mice in the pole test or increase the catalepsy time, while haloperidol (0.3-3mg/kg, p.o.) caused pronounced bradykinesia and catalepsy. Blonanserin and haloperidol at the above doses significantly enhanced Fos expression in the shell (AcS) region of the nucleus accumbens and dorsolateral striatum (dlST). The extent of blonanserin-induced Fos expression in the AcS was comparable to that induced by haloperidol. However, the striatal Fos expression by blonanserin was less prominent as compared to haloperidol. Furthermore, combined treatment of AD-6048 (0.1-3mg/kg, s.c.) with haloperidol (0.5mg/kg, i.p.) significantly attenuated haloperidol-induced bradykinesia and catalepsy. The present results show that blonanserin behaves as an atypical antipsychotic both in inducing EPS and enhancing forebrain Fos expression. In addition, AD-6048 seems to contribute at least partly to the atypical properties of blonanserin.
authors.affiliation: Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan. yohno@gly.oups.ac.jp
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ohno
authors.forename: Motoki
authors.initials: M
authors.lastname: Okano
authors.forename: Junta
authors.initials: J
authors.lastname: Imaki
authors.forename: Ayaka
authors.initials: A
authors.lastname: Tatara
authors.forename: Takahiro
authors.initials: T
authors.lastname: Okumura
authors.forename: Saki
authors.initials: S
authors.lastname: Shimizu
mesh_terms: D000818:Animals; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D002375:Catalepsy / Q000139:chemically induced / Q000188:drug therapy; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D065127:Dopamine D2 Receptor Antagonists; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004409:Dyskinesia, Drug-Induced / Q000188:drug therapy* / Q000378:metabolism; D006220:Haloperidol / Q000037:antagonists & inhibitors / Q000494:pharmacology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism; D010879:Piperazines / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology*; D010880:Piperidines / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D011725:Pyridines / Q000008:administration & dosage / Q000494:pharmacology*; D058830:Serotonin 5-HT2 Receptor Antagonists
chemical_list: C552348:AD 6048; D014150:Antipsychotic Agents; D065127:Dopamine D2 Receptor Antagonists; D010879:Piperazines; D010880:Piperidines; D016760:Proto-Oncogene Proteins c-fos; D011725:Pyridines; D058830:Serotonin 5-HT2 Receptor Antagonists; C079310:blonanserin; D006220:Haloperidol