DRD2 and schizophrenia: To discuss these issues, we will summarize various datasets of DRD2 itself, as well as several receptor-interacting proteins such as G protein-coupled receptor kinase (GRK), β-arrestin, dopamine-and cyclic adenosine monophosphate (cAMP)-regulated phosphoprotein of 32 kDa (DARPP-32), protein kinase v-akt murine thymoma viral oncogene homolog AKT, glycogen synthase kinase-3 (GSK-3), and clathrin, tracing these from the basic and clinical research fields relevant to schizophrenia and the actions of antipsychotics.