Since transcripts exhibiting a sustained change in response to cocaine are included in Clusters i (sustained increase), ii (increase, Withdrawal), and v (sustained decrease), we used Panther Pathway (Table 2A and Table S3) analysis to identify common pathways. Three pathways were enriched (P < 0.005) in these three Clusters: cadherin signaling, heterotrimeric G-protein signaling (Gαi and Gαs-mediated), and Wnt signaling; since there was a great deal of overlap in the cadherin and Wnt signaling pathways, they are discussed together. Other pathways were unique to specific clusters (Table S3). For example, components of the ionotropic glutamate receptor, metabotropic glutamate receptor group III, and nicotinic acetylcholine receptor pathways were enriched only in Cluster i (sustained increase) while components of the muscarinic acetylcholine receptor 1 and 3 pathway were enriched in Cluster ii (increase, Withdrawal).
