Midbrain acetylcholine and glutamate receptors modulate accumbal dopamine release

This study determined the role of ventral tegmental area acetylcholine and glutamate receptors in modulating laterodorsal tegmentum stimulation-evoked dopamine efflux in the nucleus accumbens. Rapid changes in dopamine oxidation current were measured at carbon fiber microelectrodes using fixed potential amperometry in urethane anesthetized male mice. Intraventral tegmental area infusions of the muscarinic acetylcholine receptor antagonist scopolamine, the nicotinic acetylcholine receptor antagonist mecamylamine, or the ionotropic glutamate receptor antagonist kynurenate significantly diminished dopamine efflux in the nucleus accumbens evoked by brief electrical stimulation of the laterodorsal tegmentum. These findings suggest that acetylcholine and ionotropic glutamate receptors influence rapid dopaminergic activity and thus the communication of behaviorally relevant information from ventral tegmental area dopamine cells to forebrain areas.