A mGluR5 antagonist under clinical development improves L-DOPA-induced dyskinesia in parkinsonian rats and monkeys

Neurobiol Dis. 2010 Sep;39(3):352-61. doi: 10.1016/j.nbd.2010.05.001. Epub 2010 May 7.

Abstract

L-DOPA remains the gold-standard treatment for Parkinson's disease but causes motor fluctuations and dyskinesia. Metabotropic glutamate receptor type 5 (mGluR5) has been proposed as a target for antidyskinetic therapies. Here, we evaluate the effects of fenobam, a noncompetitive mGluR5 antagonist already tested in humans, using rodent and nonhuman primate models of Parkinson's disease. In both animal models, acute administration of fenobam attenuated the L-DOPA-induced abnormal involuntary movements (50-70% reduction at the doses of 30mg/kg in rats and 10mg/kg in monkeys). The effect consisted in a reduction of peak-dose dyskinesia, whereas the end-dose phase was not affected. Chronic administration of fenobam to previously drug-naïve animals (de novo treatment) attenuated the development of peak-dose dyskinesia without compromising the anti-parkinsonian effect of L-DOPA. In addition, fenobam prolonged the motor stimulant effect of L-DOPA. We conclude that fenobam acts similarly in rat and primate models of L-DOPA-induced dyskinesia and represents a good candidate for antidyskinetic treatment in Parkinson's disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Disease Models, Animal
  • Dyskinesia, Drug-Induced / drug therapy*
  • Dyskinesia, Drug-Induced / etiology
  • Female
  • Imidazoles / therapeutic use*
  • Levodopa / adverse effects*
  • Macaca mulatta
  • Male
  • Oxidopamine
  • Parkinson Disease, Secondary / chemically induced
  • Parkinson Disease, Secondary / drug therapy*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Metabotropic Glutamate / antagonists & inhibitors*

Substances

  • Imidazoles
  • Receptors, Metabotropic Glutamate
  • fenobam
  • Levodopa
  • Oxidopamine