Enhancement of dopamine release from the striatum through metabotropic glutamate receptor activation in methamphetamine sensitized rats.

An intracerebral microdialysis technique was applied to study the effect of metabotropic glutamate receptor (mGluR) agonist on dopamine release in the striatum of methamphetamine (MAP)-sensitized rats. Rats were treated with MAP (1 mg/kg, i.p.) once daily for 6 consecutive days, followed by a 6-day withdrawal. Perfusion of 0.1 mM (1S,3R)-1-aminocyclopentane-trans-1,3-dicarboxylic acid through a microdialysis probe placed in the striatum enhanced the extracellular dopamine level, and induced stereotyped behavior in MAP-sensitized rats. The enhancement of dopamine release and the stereotyped behavior were attenuated by co-perfusion of 0.4 mM RS-alpha-methyl-4-carboxyphenyl-glycine, a mGluR antagonist. The present results suggest that mGluRs may be involved in the expression of MAP-induced sensitization.