DRD5

G protein-coupled receptor for dopamine, a catecholamine neurotransmitter hormone that functions as the brain's 'reward chemical', driving motivation, reinforcement learning and pleasure. Dopamine binding causes a conformation change that triggers signalling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of downstream effectors, such as adenylate cyclase. Dopamine receptors can be classified in two categories: (1) DRD5 (together with DRD1) is a D1-type receptor and is coupled to G(s) G proteins, mediating activation of adenylate cyclase activity, while D2-type receptors (DRD2, DRD3 and DRD4) are coupled to G(i)/G(o) G proteins and promote inhibition of adenylate cyclase activity. D1- and D2-type dopamine receptors have antagonistic effects, particularly in the brain's striatum, where they govern voluntary movement and reward: D1-type receptors generally stimulate neural activity and promotes action, while D2-type receptors tend to inhibit neural activity and suppress movement. DRD5 acts as a key regulator of blood pressure: negatively regulates the renin-angiotensin system (RAS), thereby reducing renal sodium absorption by the kidney. Location: Cell membrane (UniProt). Locus 4p16.1 (HGNC).