PT  - JOURNAL ARTICLE
AU  - Thomas S. Hnasko
AU  - Gregory O. Hjelmstad
AU  - Howard L. Fields
AU  - Robert H. Edwards
TI  - Ventral Tegmental Area Glutamate Neurons: Electrophysiological Properties and Projections
AID  - 10.1523/JNEUROSCI.3128-12.2012
DP  - 2012 Oct 24
TA  - The Journal of Neuroscience
PG  - 15076--15085
VI  - 32
IP  - 43
4099  - http://www.jneurosci.org/content/32/43/15076.short
4100  - http://www.jneurosci.org/content/32/43/15076.full
SO  - J. Neurosci.2012 Oct 24; 32
AB  - The ventral tegmental area (VTA) has a central role in the neural processes that underlie motivation and behavioral reinforcement. Although thought to contain only dopamine and GABA neurons, the VTA also includes a recently discovered population of glutamate neurons identified through the expression of the vesicular glutamate transporter VGLUT2. A subset of VGLUT2+ VTA neurons corelease dopamine with glutamate at terminals in the NAc, but others do not express dopaminergic markers and remain poorly characterized. Using transgenic mice that express fluorescent proteins in distinct cell populations, we now find that both dopamine and glutamate neurons in the medial VTA exhibit a smaller hyperpolarization-activated current (Ih) than more lateral dopamine neurons and less consistent inhibition by dopamine D2 receptor agonists. In addition, VGLUT2+ VTA neurons project to the nucleus accumbens (NAc), lateral habenula, ventral pallidum (VP), and amygdala. Optical stimulation of VGLUT2+ projections expressing channelrhodopsin-2 further reveals functional excitatory synapses in the VP as well as the NAc. Thus, glutamate neurons form a physiologically and anatomically distinct subpopulation of VTA projection neurons.