Dopamine receptor D2, Dopamine receptor D3, and Dopamine receptor D4 (D2-like receptors)

The Dopamine D2-like receptor family, comprising the D2, D3, and D4 subtypes, are G protein-coupled receptors (GPCRs) that primarily couple to Gi/o proteins to inhibit adenylyl cyclase and reduce intracellular cAMP levels (StatPearls, 2023; NIH, 2011). These receptors are widely distributed in the brain, particularly in the striatum, limbic system, and cortex, where they modulate motor function, reward, and cognition (Wikipedia, 2024; UniProt, 2024). D2 receptors are the primary target for antipsychotic medications, which act as antagonists or partial agonists to alleviate symptoms of schizophrenia (Frontiers in Pharmacology, 2020). D3 and D4 receptors are also implicated in psychiatric disorders and are targets for newer atypical antipsychotics and treatments for Parkinson's disease (NIH, 2011; Wikipedia, 2024). Dysregulation of these receptors is central to the pathophysiology of Parkinson's disease, schizophrenia, and addiction (StatPearls, 2023). Therapeutic modulation of these receptors requires a careful balance, as excessive D2 blockade can lead to extrapyramidal symptoms and hyperprolactinemia, while D3 agonism is associated with impulse control disorders (NIH, 2011; StatPearls, 2023).

Other names

D2-like receptorsDRD2DRD3DRD4D2RD3RD4RDopamine D2 receptorDopamine D3 receptorDopamine D4 receptor

Antagonism of D2-like receptors to reduce dopaminergic overactivity in schizophrenia; agonism or partial agonism to treat Parkinson's disease and stabilize dopamine levels in mood disorders.