Neuron
Volume 75, Issue 1, 12 July 2012, Pages 58-64
Journal home page for Neuron

Report
Striatal Dopamine Release Is Triggered by Synchronized Activity in Cholinergic Interneurons

https://doi.org/10.1016/j.neuron.2012.04.038Get rights and content
Under an Elsevier user license
open archive

Summary

Striatal dopamine plays key roles in our normal and pathological goal-directed actions. To understand dopamine function, much attention has focused on how midbrain dopamine neurons modulate their firing patterns. However, we identify a presynaptic mechanism that triggers dopamine release directly, bypassing activity in dopamine neurons. We paired electrophysiological recordings of striatal channelrhodopsin2-expressing cholinergic interneurons with simultaneous detection of dopamine release at carbon-fiber microelectrodes in striatal slices. We reveal that activation of cholinergic interneurons by light flashes that cause only single action potentials in neurons from a small population triggers dopamine release via activation of nicotinic receptors on dopamine axons. This event overrides ascending activity from dopamine neurons and, furthermore, is reproduced by activating ChR2-expressing thalamostriatal inputs, which synchronize cholinergic interneurons in vivo. These findings indicate that synchronized activity in cholinergic interneurons directly generates striatal dopamine signals whose functions will extend beyond those encoded by dopamine neuron activity.

Highlights

► Striatal ACh input to dopamine axons directly evokes dopamine release via nAChRs ► DA release is triggered by synchrony amongst cholinergic interneurons (ChIs) ► ChI-driven DA release overrides ascending input from dopamine neurons ► ACh interneurons and their inputs are potential targets for treatment of DA disorders

Cited by (0)