title: Opiate binding sites in the chick, rabbit and goldfish retina.
abstract: The characteristics of opiate binding sites in the retina of the chick, rabbit and goldfish have been investigated. In the newly hatched chick retina, 131 fmol/mg of binding sites for [D-Ala2-D-Leu5]-[3H]enkephalin are present; competition studies with the delta selective peptide [D-Thr-Leu5]-enkephalin (DTLET) and the mu selective peptide morphiceptin show that all of the [D-Ala2-D-Leu5]-[3H]-enkephalin binding sites are of the delta subtype. Dihydro[3H]morphine binds poorly to the chick retina; 13.2 fmol/mg of this binding is displaceable by morphiceptin and corresponds to mu binding sites. Benzomorphan sites are defined as sites occupied by [3H]diprenorphine which is displaceable by low concentrations of ethylketocyclozacine but not by high concentrations of D-Ala2-D-Leu5-enkephalin and morphiceptin. At least 88 fmol/mg of benzomorphan sites are present in the chick retina. [3H]diprenorphine binding to the rabbit and fish retina was measured. The rabbit retina bound 60 fmol/mg, and the fish retina 42 fmol/mg of [3H]diprenorphine. These findings are discussed in the light of the studies on the localization and physiological effects of enkephalin in the retina.
authors.forename: M M
authors.initials: MM
authors.lastname: Slaughter
authors.forename: J A
authors.initials: JA
authors.lastname: Mattler
authors.forename: D I
authors.initials: DI
authors.lastname: Gottlieb
mesh_terms: D000818:Animals; D001575:Benzomorphans / Q000378:metabolism; D002645:Chickens; D004090:Dihydromorphine / Q000378:metabolism; D004174:Diprenorphine / Q000378:metabolism; D004723:Endorphins / Q000378:metabolism; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000378:metabolism; D016308:Enkephalin, Leucine-2-Alanine; D006054:Goldfish; D009842:Oligopeptides / Q000378:metabolism; D011817:Rabbits; D011957:Receptors, Opioid / Q000032:analysis*; D012160:Retina / Q000032:analysis*; D013045:Species Specificity
chemical_list: D001575:Benzomorphans; D004723:Endorphins; D009842:Oligopeptides; D011957:Receptors, Opioid; D004174:Diprenorphine; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; C037653:deltakephalin; C028889:morphiceptin; D004090:Dihydromorphine