Cocaine addiction-like behaviors are associated with long-term changes in gene regulation, energy metabolism, and GABAergic inhibition within the amygdala

Abstract

AbstractThe amygdala contributes to negative emotional states associated with relapse to drug seeking, but the cell type-specific gene regulatory programs that are involved in addiction are unknown. Here we generate an atlas of single nucleus gene expression and chromatin accessibility in the amygdala of outbred rats with low and high cocaine addiction-like behaviors following a prolonged period of abstinence. Between rats with different addiction indexes, there are thousands of cell type-specific differentially expressed genes and these are enriched for molecular pathways including GABAergic synapse in astrocytes, excitatory, and somatostatin neurons. We find that rats with higher addiction severity have excessive GABAergic inhibition in the amygdala, and that hyperpolarizing GABAergic transmission and relapse-like behavior are reversed by pharmacological manipulation of the metabolite methylglyoxal, a GABAA receptor agonist. By analyzing chromatin accessibility, we identify thousands of cell type-specific chromatin sites and transcription factor (TF) motifs where accessibility is associated with addiction-like behaviors, most notably at motifs for pioneer TFs in the FOX, SOX, and helix-loop-helix families.