title: Separation of kappa-opioid receptor subtype from frog brain.
abstract: Complete separation of the [3H]ethylketocyclazocine [( 3H]EKC) specific binding (kappa subtype) from tritiated Tyr-D-Ala2-Me-Phe4-Gly-ol5 enkephalin (DAGO) and Tyr-D-Ala2-L-Leu5-enkephalin (DALA) binding (mu-and delta-subtypes, respectively) was achieved by Sepharose-6B chromatography and sucrose density gradient centrifugation of digitonin solubilized frog brain membranes. The apparent sedimentation coefficient (s20.w) for the kappa receptor-detergent complex was 13.1 S and the corresponding Stokes radius 64 A. The isolated fractions exhibited high affinity for EKC and bremazocine, whereas mu- and delta-specific ligands were unable to compete for the [3H]EKC binding sites, indicating that the kappa subtype represents a separate molecular to compete for the [3H]EKC binding sites, indicating that the kappa subtype represents a separate molecular entity from the mu and delta receptor sites.
authors.forename: J
authors.initials: J
authors.lastname: Simon
authors.forename: S
authors.initials: S
authors.lastname: Benyhe
authors.forename: A
authors.initials: A
authors.lastname: Borsodi
authors.forename: M
authors.initials: M
authors.lastname: Szücs
authors.forename: M
authors.initials: M
authors.lastname: Wollemann
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D002499:Centrifugation, Density Gradient; D002850:Chromatography, Gel; D003496:Cyclazocine / Q000031:analogs & derivatives / Q000378:metabolism; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives / Q000378:metabolism; D004745:Enkephalins / Q000378:metabolism; D016314:Ethylketocyclazocine; D011893:Rana esculenta; D011957:Receptors, Opioid / Q000302:isolation & purification*; D017473:Receptors, Opioid, kappa
chemical_list: D004745:Enkephalins; D011957:Receptors, Opioid; D017473:Receptors, Opioid, kappa; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004744:Enkephalin, Methionine; D016314:Ethylketocyclazocine; C022118:enkephalinamide-Met, Ala(2)-; D003496:Cyclazocine