Dopamine receptor D1-D4 family (DRD1-DRD4)

The Dopamine D1–D4 receptor family consists of G protein-coupled receptors (GPCRs) that mediate the physiological actions of the neurotransmitter dopamine within the central nervous system and peripheral tissues. These receptors are traditionally categorized into two classes based on their biochemical signaling: the D1-like family (which includes D1) and the D2-like family (comprising D2, D3, and D4). D1 receptors typically couple to Gs proteins to stimulate adenylyl cyclase activity, whereas D2, D3, and D4 receptors couple to Gi/o proteins to inhibit it. This receptor family is fundamental to the regulation of voluntary movement, reward-seeking behavior, motivation, and complex cognitive processes such as working memory. Dysregulation of these receptors is a hallmark of several major neuropsychiatric disorders, including schizophrenia, Parkinson's disease, and ADHD. Pharmacological management of these conditions involves the use of dopamine receptor antagonists to treat psychosis or agonists to alleviate motor symptoms in neurodegenerative diseases (UniProt: DRD1, DRD2, DRD3, DRD4 [3]; NIH: Parkinson's Disease [4]; PubMed: The dopamine hypothesis of schizophrenia [5]).

Other names

Dopamine receptorsDopaminergic receptorsDA receptorsDRD1DRD2DRD3DRD4

Dopamine receptors are targeted by agonists to mimic dopamine and restore signaling in deficiency states like Parkinson's disease, or by antagonists to block overactive signaling in conditions like schizophrenia. D1-like receptors (D1) typically stimulate adenylyl cyclase via Gs/olf proteins, while D2-like receptors (D2, D3, D4) inhibit adenylyl cyclase via Gi/o proteins. Partial agonists, such as aripiprazole, provide a stabilizing effect by acting as functional antagonists in high-dopamine environments and agonists in low-dopamine environments (StatPearls: Physiology, Dopamine Receptors [1]; IUPHAR/BPS Guide to Pharmacology [2]).