title: [3H]AHN 086 acylates peripheral benzodiazepine receptors in the rat pineal gland.
abstract: AHN 086, an isothiocyanato derivative of Ro 5-4864 (4'-chlorodiazepam), inhibits radioligand binding to peripheral benzodiazepine receptors with characteristics of an irreversible (acylating) ligand. We now report that [3H]AHN 086 labels a approximately 30 kDa protein in the rat pineal gland determined by both SDS-polyacrylamide gel electrophoresis and gel filtration high-performance liquid chromatography of digitonin-solubilized membranes. Specific incorporation of [3H]AHN 086 into this protein was inhibited by preincubating membranes with excess AHN 086. Moreover, significant specific binding of [3H]AHN 086 was not observed in either bovine pineal gland (which does not possess high-affinity binding sites for Ro 5-4864) or ovalbumin. These findings suggest that the approximately 30 kDa protein labeled by [3H]AHN 086 in rat pineal gland is associated with peripheral benzodiazepine receptors in this tissue.
authors.affiliation: Laboratory of Neuroscience, NIDDK, Bethesda, MD 20892.
authors.forename: R T
authors.initials: RT
authors.lastname: McCabe
authors.forename: J A
authors.initials: JA
authors.lastname: Schoenheimer
authors.forename: P
authors.initials: P
authors.lastname: Skolnick
authors.forename: A H
authors.initials: AH
authors.lastname: Newman
authors.forename: K C
authors.initials: KC
authors.lastname: Rice
authors.forename: J A
authors.initials: JA
authors.lastname: Reig
authors.forename: D C
authors.initials: DC
authors.lastname: Klein
mesh_terms: D000215:Acylation; D000818:Animals; D001570:Benzodiazepinones / Q000378:metabolism*; D002417:Cattle; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D008297:Male; D008970:Molecular Weight; D010870:Pineal Gland / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000302:isolation & purification / Q000378:metabolism*; D014316:Tritium
chemical_list: D001570:Benzodiazepinones; D011963:Receptors, GABA-A; D014316:Tritium; C049442:AHN 086