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bioRxiv · 10.1101/475343

Divergent mesolimbic dopamine circuits support alcohol-seeking triggered by discrete cues and contexts

Valyear, M. D.·Glovaci, I.·Zaari, A.·Lahlou, S.·Trujillo-Pisanty, I.·Chapman, C. A.·Chaudhri, N.
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Abstract

Discrete and contextual cues that predict alcohol trigger alcohol-seeking. However, the extent to which context influences alcohol-seeking triggered by discrete cues, and the neural mechanisms underlying these responses, are not well known. We show that, relative to a neutral context, a context associated with alcohol persistently elevated alcohol-seeking triggered by a discrete cue, and supported higher levels of priming-induced reinstatement. Alcohol-seeking triggered by a discrete cue in a neutral context was reduced by designer receptor-mediated inhibition of ventral tegmental area (VTA) dopamine neurons in TH::Cre rats. Inhibiting terminals of VTA dopamine neurons in the nucleus accumbens (NAc) core reduced alcohol-seeking triggered by a discrete cue, irrespective of context, whereas inhibiting VTA dopamine terminals in the NAc shell selectively reduced the elevation of alcohol-seeking triggered by a discrete cue in an alcohol context. This dissociation highlights unique roles for divergent mesolimbic dopamine circuits in alcohol-seeking driven by discrete and contextual environmental cues.

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Valyear, M. D., Glovaci, I., Zaari, A., Lahlou, S., Trujillo-Pisanty, I., Chapman, C. A., Chaudhri, N.. 2018-11-29. Divergent mesolimbic dopamine circuits support alcohol-seeking triggered by discrete cues and contexts. https://doi.org/10.1101/475343

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