Comparison of the mGlu(5) receptor positive allosteric modulator ADX47273 and the mGlu(2/3) receptor agonist LY354740 in tests for antipsychotic-like activity

Eur J Pharmacol. 2009 Nov 25;623(1-3):73-83. doi: 10.1016/j.ejphar.2009.09.006. Epub 2009 Sep 16.

Abstract

Recently, it has been proposed that activation of either metabotropic glutamate receptors e.g. mGlu(5) by positive allosteric modulators or stimulation of mGluR(2/3) receptors by agonists may offer new strategy in schizophrenia treatment. The aim of the present study was to compare the effect of mGlu(5) receptor positive allosteric modulator, ADX47273 (S-(4-Fluoro-phenyl)-{3-[3-(4-fluoro-phenyl)-[1,2,4]oxadiazol-5-yl]-piperidin-1-yl}-methanone), mGluR(2/3) agonist, LY354740 ((1S,2S,5R,6S)-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylate monohydrate) and selected neuroleptics in animal models for positive schizophrenia symptoms. ADX47273 (3 and 10mg/kgi.p.), the typical antipsychotic haloperidol (0.1 and 0.2mg/kgi.p.), the atypical antipsychotics aripiprazole (1.25-5mg/kgi.p.) and olanzapine (2.5 and 5mg/kgi.p.) all reduced amphetamine-induced hyperlocomotion in Sprague-Dawley rats, unlike the mGlu(2/3) receptor agonist LY354740 (1-10mg/kgi.p.). Interestingly, haloperidol (0.1 and 0.2mg/kgi.p.), aripiprazole (1.25-5mg/kgi.p.) and olanzapine (1.25-5mg/kgi.p.), but not ADX47273 (1-10mg/kgi.p.), all reduced spontaneous locomotion and rearings at doses effective against amphetamine-induced hyperlocomotion. This indicates that the effect of ADX47273 in combination with amphetamine may be specific, and also suggests a lack of sedative side effects. Moreover, ADX47273 (30mg/kgi.p.), haloperidol (0.1 and 0.2mg/kgi.p.) and aripiprazole (5 and 10mg/kgi.p.) reversed apomorphine (0.5mg/kgs.c.)-induced deficits of prepulse inhibition, whereas neither LY354740 (1-10mg/kgi.p.) nor olanzapine (1.25-5mg/kgi.p.) produced this effect. Lack of effect of olanzapine was unexpected and at present no convincing explanation can be provided. In conclusion, in selected rodent models for positive schizophrenia symptoms, ADX47273 showed better efficacy than LY354740.

Publication types

  • Comparative Study

MeSH terms

  • Allosteric Regulation
  • Animals
  • Antipsychotic Agents / pharmacology
  • Antipsychotic Agents / therapeutic use*
  • Behavior, Animal / drug effects
  • Bridged Bicyclo Compounds / therapeutic use*
  • Dopamine Agents / pharmacology
  • Dose-Response Relationship, Drug
  • Excitatory Amino Acid Agents / pharmacokinetics
  • Excitatory Amino Acid Agents / therapeutic use*
  • Excitatory Amino Acid Agonists / therapeutic use*
  • Male
  • Motor Activity / drug effects
  • Neural Inhibition / drug effects
  • Oxadiazoles / pharmacokinetics
  • Oxadiazoles / therapeutic use*
  • Piperidines / pharmacokinetics
  • Piperidines / therapeutic use*
  • Rats
  • Rats, Sprague-Dawley
  • Receptor, Metabotropic Glutamate 5
  • Receptors, Metabotropic Glutamate / agonists*
  • Receptors, Metabotropic Glutamate / metabolism*
  • Reflex, Startle / drug effects
  • Schizophrenia / chemically induced
  • Schizophrenia / drug therapy
  • Treatment Outcome

Substances

  • Antipsychotic Agents
  • Bridged Bicyclo Compounds
  • Dopamine Agents
  • Excitatory Amino Acid Agents
  • Excitatory Amino Acid Agonists
  • Oxadiazoles
  • Piperidines
  • Receptor, Metabotropic Glutamate 5
  • Receptors, Metabotropic Glutamate
  • S-(4-fluorophenyl)-(3-(3-(4-fluorophenyl)-(1,2,4)-oxadiazol-5-yl)piperidin-1-yl)methanone
  • eglumetad