Nature Reviews Neuroscience 9, 326. May 2008 | doi:10.1038/nrn2381
The ventral tegmental area contains two distinct types of dopaminergic neuron.
Dopamine is a versatile neurotransmitter that has a role in movement and many aspects of cognition. Lammel et al. have now characterized two types of neurons in the mesocorticolimbic dopamine system that are not only anatomically segregated, with non-overlapping axonal target regions, but that also have distinct molecular and functional properties. This structured diversity of the dopamine midbrain system might contribute to the multiplicity of dopamine functions in the CNS.
Dopamine pathways in the brain are generally divided into the well-characterized mesostriatal system, which originates in the substantia nigra pars compacta (SNc) and projects to the dorsal striatum, and the mesocorticolimbic system, which starts in the ventral tegmental area (VTA) and projects to the frontal cortex and limbic areas including the amygdala and the nucleus accumbens (NAc). By retrogradely tracing mesocorticolimbic dopamine neurons, the authors established that dopamine projections in the medial prefrontal cortex, the basolateral amygdala and the core and medial shell of the NAc originate in the medial posterior part of the VTA, whereas dopamine projections to the lateral shell of the NAc originate in the more lateral portions of the VTA and the medial part of the SNc.
ORIGINAL RESEARCH PAPER
Lammel, S. et al. Unique properties of mesoprefrontal neurons within a dual mesocorticolimbic dopamine system. Neuron 57, 760–773 (2008). Pubmed