Dopamine receptor D1, Dopamine receptor D2, Dopamine receptor D3 (DRD1, DRD2, DRD3)

Dopamine receptors D1, D2, and D3 are members of the G protein-coupled receptor (GPCR) superfamily, mediating the effects of the neurotransmitter dopamine across different regions of the central nervous system and peripheral tissues. They are classified by structure and signaling into D1-like (D1, D5) and D2-like (D2, D3, D4) receptor subfamilies. D1 (encoded by DRD1) primarily couples to Gs proteins, stimulating adenylyl cyclase and increasing cAMP; D2 (DRD2) and D3 (DRD3) primarily couple to Gi/Go proteins, inhibiting adenylyl cyclase and decreasing cAMP levels. D1 is the most abundant, widely distributed in the brain; D2 is highly expressed in the striatum as well as other subcortical regions; D3 is more selectively expressed, especially in the limbic system. These receptors are implicated in the regulation of motor control, cognition, reward, endocrine signaling, and are central to the pharmacology of many psychiatric and neurological diseases, with numerous drugs targeting these sites for the treatment of Parkinson’s disease, schizophrenia, depression, and other disorders. Note: For data granularity and downstream structuring, it is critical to split this target into three entries: one for each receptor (Dopamine receptor D1, Dopamine receptor D2, Dopamine receptor D3). The grouping here is non-canonical and does not map to a unique molecular entity but, instead, to related but distinct GPCR proteins.

Other names

D1 receptorD2 receptorD3 receptorD1-like receptor (for D1 and D5)D2-like receptor (for D2, D3, D4)dopamine receptorsDA receptors

Agonism (directly stimulating receptor activity) - Antagonism (blocking receptor activity) - Partial agonism (partial stimulation) - Modulation of second messenger systems (cAMP, PLC, different based on subfamily)