D4 dopamine receptor of the D2-like family, member of the class A family of seven-transmembrane G protein-coupled receptors
Dopamine receptors are members of the class A G protein-coupled receptors that are involved in many neurological processes in the central nervous system (CNS). The neurotransmitter dopamine is the primary endogenous agonist for dopamine receptors. Dopamine receptors consist of at least five subtypes: D1, D2, D3, D4, and D5. The D1 and D5 subtypes are members of the D1-like family of dopamine receptors, whereas the D2, D3 and D4 subtypes are members of the D2-like family. Activation of D2-like family receptors is linked to G proteins of the G(i) family. This leads to a decrease in adenylate cyclase activity, thereby decreasing cAMP levels. Dopamine receptors are major therapeutic targets for neurological and psychiatric disorders such as drug abuse, depression, schizophrenia, or Parkinson's disease.