title: Presence and characterization of nociceptin (orphanin FQ) receptor binding in adult rat and human fetal hypothalamus.
abstract: High affinity and saturable nociceptin (orphanin FQ) receptors were detected and characterized in adult rat and human fetal hypothalamic membranes, utilizing [125I]Tyr12-nociceptin as ligand. Nociceptin bound with picomolar affinity, dynorphin A with nanomolar affinity, naloxone and dynorphan A(1-8) with micromolar while des-Tyr1-dynorphin (dynorphin A(2-17)), several other opioids, morphine and benzomorphans failed to compete for binding at 1-10 microM. Gpp(NH)p together with sodium ion markedly decreased binding, consistent with involvement of a G protein-linked receptor.
authors.affiliation: Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
authors.forename: M H
authors.initials: MH
authors.lastname: Makman
authors.forename: W D
authors.initials: WD
authors.lastname: Lyman
authors.forename: B
authors.initials: B
authors.lastname: Dvorkin
mesh_terms: D000818:Animals; D001667:Binding, Competitive / Q000502:physiology; D005260:Female; D005333:Fetus / Q000737:chemistry; D019204:GTP-Binding Proteins / Q000378:metabolism; D006801:Humans; D007031:Hypothalamus / Q000737:chemistry* / Q000196:embryology; D007457:Iodine Radioisotopes; D008297:Male; D011869:Radioligand Assay; D051381:Rats; D017207:Rats, Sprague-Dawley; D011957:Receptors, Opioid / Q000032:analysis* / Q000378:metabolism; D000094942:Nociceptin Receptor
chemical_list: D007457:Iodine Radioisotopes; D011957:Receptors, Opioid; D019204:GTP-Binding Proteins; D000094942:Nociceptin Receptor