title: Late evolutionary appearance of 'peripheral-type' binding sites for benzodiazepines.
abstract: Four classes of non-mammalian vertebrates were examined for the presence of both 'brain-specific' and 'peripheral-type' binding sites for benzodiazepines in the central nervous system. 'Brain-specific' binding sites for benzodiazepines were found in the central nervous systems of all non-mammalian vertebrates studied. However, in contrast to mammals, either very low or undetectable levels of 'peripheral-type' binding sites for benzodiazepines were observed in the central nervous systems of these non-mammalian vertebrates. Furthermore, the density of 'peripheral-type' binding sites for benzodiazepines in non-mammalian vertebrate heart was less than or equal to 2% of that found in mammalian cardiac tissue. These findings suggest a very late evolutionary appearance of 'peripheral-type' binding sites for benzodiazepines, implying that these sites may have (a) highly specialized function(s) in both peripheral tissues and the central nervous system.
authors.forename: G T
authors.initials: GT
authors.lastname: Bolger
authors.forename: B A
authors.initials: BA
authors.lastname: Weissman
authors.forename: H
authors.initials: H
authors.lastname: Lueddens
authors.forename: A S
authors.initials: AS
authors.lastname: Basile
authors.forename: C R
authors.initials: CR
authors.lastname: Mantione
authors.forename: J E
authors.initials: JE
authors.lastname: Barrett
authors.forename: J M
authors.initials: JM
authors.lastname: Witkin
authors.forename: S M
authors.initials: SM
authors.lastname: Paul
authors.forename: P
authors.initials: P
authors.lastname: Skolnick
mesh_terms: D000818:Animals; D001570:Benzodiazepinones / Q000378:metabolism; D005075:Biological Evolution; D001923:Brain Chemistry; D010856:Columbidae; D005445:Flunitrazepam / Q000378:metabolism; D008116:Lizards; D008297:Male; D009928:Organ Specificity; D011869:Radioligand Assay; D011892:Rana catesbeiana; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000032:analysis*; D014337:Trout; D014714:Vertebrates / Q000378:metabolism*
chemical_list: D001570:Benzodiazepinones; D011963:Receptors, GABA-A; C028513:4'-chlorodiazepam; D005445:Flunitrazepam