RT Journal Article SR Electronic T1 Habituation Deficits Induced by Metabotropic Glutamate Receptors 2/3 Receptor Blockade in Mice: Reversal by Antipsychotic Drugs JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 944 OP 950 DO 10.1124/jpet.106.110684 VO 320 IS 2 A1 Anton Bespalov A1 Ana-Lucia Jongen-Rêlo A1 Marcel van Gaalen A1 Silke Harich A1 Hans Schoemaker A1 Gerhard Gross YR 2007 UL http://jpet.aspetjournals.org/content/320/2/944.abstract AB Cortical metabotropic glutamate receptors (mGluRs) seem to be involved in habituation of simple stimulus-bound behaviors (e.g., habituation to acoustic startle or odor-elicited orienting response). Habituation deficits may contribute to the cognitive symptoms of schizophrenia. In the present study, male NMRI mice were injected with mGluR2/3 antagonist 2S-2-amino-2-(1S,2S-2-carboxycyclopropyl-1-yl)-3-(xanth-9-yl)propanoic acid (LY-341495) 30 min before being placed into novel arenas for automatic motor activity recording (2-h sessions). Administration of LY-341495 (1–10 mg/kg s.c.) dose-dependently prevented the habituation of the locomotor activity. Effects of LY-341495 (10 mg/kg) were fully and dose-dependently reversed by i.p. administration of haloperidol (0.03–0.3 mg/kg), clozapine (1–10 mg/kg), risperidone (0.01–0.1 mg/kg), olanzapine (0.3–3 mg/kg), aripiprazole (1–10 mg/kg), and sulpiride (3–30 mg/kg), each of which was given 15 min before the test. Effects of antipsychotic drugs were observed at the dose levels that did not affect spontaneous motor activity. LY-341495-induced delayed hyperactivity was also partially attenuated by lithium (50–200 mg/kg), amisulpride (1–10 mg/kg), and the selective dopamine D3 antagonist trans-N-[4-[2-(6-cyano-1,2,3,4-tetrahydroisoquinolin-2-yl)ethyl]cyclohexyl]-4-quinolin-ecarboxamide (SB-277011A; 3–30 mg/kg). Application of diazepam, imipramine, or several agonists and/or antagonists acting at various receptors that are thought to be relevant for antipsychotic treatment [e.g., 5-hydroxytryptamine (5-HT)2A, 5-HT3, and 5-HT6 antagonists; 5-HT1A agonist; D4 antagonist; CB1 antagonist; ampakines; and glycine transporter inhibitor) had no appreciable effects. Thus, behavioral deficits induced by mGluR2/3 blockade (such as delayed motor hyperactivity) are selectively reversed by clinically used antipsychotic drugs. The American Society for Pharmacology and Experimental Therapeutics