Nicotine and alcohol: the role of midbrain dopaminergic neurons in drug reinforcement. (15th October 2018)

• Record Type: Journal Article
• Authors: Morel, Carole; Montgomery, Sarah; Han, Ming‐Hu
• Is Part Of: European journal of neuroscience. Volume 50:Number 3(2019)
• Page Start: 2180
• Page End: 2200
• Publication Date: 2018-10-15
• Subjects: alcohol -- circuit -- dopamine -- electrophysiology -- heterogeneity -- nicotine -- reinforcement -- ventral tegmental area; Nervous system -- Periodicals; 612.8
• DOI: 10.1111/ejn.14160
• Languages: English
• ISSNs: 0953-816X

Abstract

Abstract: Nicotine and alcohol addiction are leading causes of preventable death worldwide and continue to constitute a huge socio‐economic burden. Both nicotine and alcohol perturb the brain's mesocorticolimbic system. Dopamine (DA) neurons projecting from the ventral tegmental area (VTA) to multiple downstream structures, including the nucleus accumbens, prefrontal cortex, and amygdala, are highly involved in the maintenance of healthy brain function. VTA DA neurons play a crucial role in associative learning and reinforcement. Nicotine and alcohol usurp these functions, promoting reinforcement of drug taking behaviors. In this review, we will first describe how nicotine and alcohol individually affect VTA DA neurons by examining how drug exposure alters the heterogeneous VTA microcircuit and network‐wide projections. We will also examine how coadministration or previous exposure to nicotine or alcohol may augment the reinforcing effects of the other. Additionally, this review briefly summarizes the role of VTA DA neurons in nicotine, alcohol, and their synergistic effects in reinforcement and also addresses the remaining questions related to the circuit‐function specificity of the dopaminergic system in mediating nicotine/alcohol reinforcement and comorbidity. Abstract : Ventral tegmental area (VTA) dopamine (DA) neurons project to multiple brain areas, including the prefrontal cortex (PFC), amygdala (AMG) and nucleus accumbens (NAc). Nicotine and alcohol induce heterogeneous reinforcing effects across the VTA. Anatomical location of DA neurons within the VTA dictates sensitivity and response to nicotine (+/−) or to alcohol (+/ +) across the anterior/posterior and medial/lateral axes.