Fig. 2. Schematic representation of the chemical structures of cocaine, ethanol, and morphine. These drugs gain rapid access to rat brain tissue, where they target several neural pathways heavily represented by dopaminergic, opioidergic, and GABAergic systems. There is considerable overlap between these functional neurotransmitter systems, which provides several potential sites at which interactions relevant to the development of drug addiction may occur. AA = amygdala; Acb = nucleus accumbens; Arc = arcuate nucleus; CdP = caudate putamen; Cer = cerebellum; FC = frontal cortex; GP = globus pallidus; H = hypothalamus; Hip = hippocampus; LC = locus ceruleus; NCx = neocortex; PAG = periaquaductal gray area; RN = raphe nucleus; SN = substantia nigra; TH = thalamus; Tu = olfactory tubercle; VTA = ventral tegmental area. Neuroanatomical nomenclature is derived, in part, from the rat atlas of Kruger et al. (213).
