title: Orphan G protein-coupled receptors in the CNS.
abstract: The majority of genes encoding G protein-coupled receptors were isolated by methods based on sequence similarities found throughout this family. Experimental techniques have exploited these similarities (including low-stringency hybridization, polymerase chain reaction and electronic database searching) to identify genes encoding many pharmacologically recognized receptors and their subtypes. Homology-based searches have revealed receptors for which the endogenous ligands were unknown and these were named orphan receptors. Many orphan receptors are expressed in the brain, suggesting the existence of unidentified neurotransmitters. Methods used to identify ligands for these orphan receptors resulted in the identification of novel ligands and succeeded in pairing previously identified ligands with their receptors. Similar successful strategies are required to characterize the physiological and pathological importance of the remaining orphan receptors to facilitate the discovery of novel drugs for these systems.
authors.affiliation: Department of Pharmacology, University of Toronto, Ontario, Canada. dennis.lee.a@utoronto.ca
authors.forename: D K
authors.initials: DK
authors.lastname: Lee
authors.forename: S R
authors.initials: SR
authors.lastname: George
authors.forename: J F
authors.initials: JF
authors.lastname: Evans
authors.forename: K R
authors.initials: KR
authors.lastname: Lynch
authors.forename: B F
authors.initials: BF
authors.lastname: O'Dowd
mesh_terms: D000818:Animals; D002490:Central Nervous System / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D011945:Receptors, Angiotensin / Q000187:drug effects / Q000378:metabolism; D043882:Receptors, Cannabinoid; D011956:Receptors, Cell Surface / Q000187:drug effects* / Q000378:metabolism; D011955:Receptors, Drug / Q000187:drug effects / Q000378:metabolism; D044088:Receptors, Galanin; D018013:Receptors, Neuropeptide / Q000187:drug effects / Q000378:metabolism; D017476:Receptors, Neuropeptide Y / Q000187:drug effects / Q000378:metabolism; D017481:Receptors, Somatostatin / Q000187:drug effects / Q000378:metabolism
chemical_list: D011945:Receptors, Angiotensin; D043882:Receptors, Cannabinoid; D011956:Receptors, Cell Surface; D011955:Receptors, Drug; D044088:Receptors, Galanin; D018013:Receptors, Neuropeptide; D017476:Receptors, Neuropeptide Y; D017481:Receptors, Somatostatin