The metabotropic glutamate receptor 8 agonist (S)-3,4-DCPG reverses motor deficits in prolonged but not acute models of Parkinson's disease

► The mGlu8 agonist DCPG fails to reverse motor deficits in acute DA depletion models. ► DCPG reverses akinesia induced by overnight (18-20 h) reserpine treatment. ► DCPG also reverses catalepsy induced by overnight haloperidol treatment. ► Haloperidol decanoate induces prolonged catalepsy and D2 receptor occupancy. ► DCPG reverses forelimb use asymmetry caused by 6-hydroxydopamine lesion of the SNc.