PKA is multifunctional and is involved in many aspects of neuronal function including synaptic plasticity,59,60 exocytosis,61 and gene transcription.62 PKA can also modulate other second-messenger pathways such as the MAPK signaling pathway.60 PKA is expressed throughout the brain, where it is particularly abundant in the cortex, thalamus, and amygdala and moderately abundant in the midbrain, NAc, and VTA.6
