Advances in studying phasic dopamine signaling in brain reward mechanisms.

The last sixty years of research has provided extraordinary advances of our knowledge of the reward system. Since its discovery as a neurotransmitter by Carlsson and colleagues (1), dopamine (DA) has emerged as an important mediator of reward processing. As a result, a number of electrochemical techniques have been developed to measure DA in the brain.

Ventral tegmental area α6β2 nicotinic acetylcholine receptors modulate phasic dopamine release in the nucleus accumbens core.

Rationale: Phasic dopamine (DA) signaling underlies reward learning. Cholinergic and glutamatergic inputs into the ventral tegmental area (VTA) are crucial for modulating burst firing activity and subsequent phasic DA release in the nucleus accumbens (NAc), but the specific VTA nicotinic receptor subtypes that regulate phasic DA release have not been identified.

Objective: The goal was to determine the role of VTA N-methyl-D-aspartate receptors (NMDARs) and specific subtypes of nicotinic acetylcholine receptors (nAChRs) in regulating phasic DA release in the NAc core.