Transcriptional plasticity of ventral tegmental area neurons induced after cessation of chronic cocaine exposure is required for incubation of cocaine seeking

Abstract

Chronic cocaine triggers changes in brain function that persist long after drug taking has ceased. Relapse to substance use during abstinence can be triggered by drug-associated cues, implicating the drug-free period after chronic cocaine as a time when the probability of relapse is modulated by plasticity mechanisms. Here, we studied the regulation and function of transcriptional plasticity activated in a time-dependent manner in dopaminergic and glutamatergic neurons of the mouse ventral tegmental area (VTA) over a drug-free period after chronic cocaine. We used in vivo dCas9/CRISPR inhibition to demonstrate a causal role for Brain-Derived Neurotrophic Factor transcription in the incubation of cocaine seeking during abstinence, and we used single-nucleus sequencing to identify a program of gene regulation induced in VTA neurons selectively by the prolonged absence of cocaine. These data advance the understanding of plasticity mechanisms that modulate reward functions of VTA neurons, which may be a main factor propagating relapse in substance use disorders.