title: Characterization of peptide YY receptors in the brain.
abstract: We studied the pharmacological and structural characteristics of peptide YY (PYY) receptors in porcine brain. PYY and neuropeptide Y (NPY) bound with high affinity to crude membrane preparations from the hippocampus, but their C-terminal fragments bound with 30- to 450-fold lower affinity Guanine nucleotides, especially the nonhydrolyzable GTP analog GTP gammas inhibited the binding of [125I]PYY, but other transmitters, hormones, and central nervous system-acting drugs did not, except for gangliosides at high concentrations. These results suggest that PYY receptor binding resides in the N-terminal part of the PYY molecule and is coupled to a guanine nucleotide regulatory protein. To elucidate PYY receptor structure, we used the cross-linking reagent disuccinimidyl suberate to covalently attach [125I]PYY to its receptors in the hippocampus membrane. Gel electrophoresis followed by autoradiography revealed a band centered at the mol wt of 50,000. Competitive inhibition of binding by unlabeled PYY resulted in a parallel inhibition of labeling of the 50,000 mol wt protein. The reducing agent 2-mercaptoethanol did not affect the appearance of this band, suggesting that the PYY receptor does not have subunits connected by sulfhydryl bonds. Furthermore, cross-linking [125I]NPY to its receptors in the porcine hippocampus produced the same 50,000 mol wt band regardless of 2-mercaptoethanol. The identity in the size of NPY and PYY receptors together with their similarities in binding properties including regional distribution and peptide specificity, indicate that NPY and PYY regulate brain function through interaction at a common receptor site.
authors.affiliation: Second Department of Internal Medicine, Kobe University School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Inui
authors.forename: M
authors.initials: M
authors.lastname: Okita
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: N
authors.initials: N
authors.lastname: Sakatani
authors.forename: M
authors.initials: M
authors.lastname: Oya
authors.forename: H
authors.initials: H
authors.lastname: Morioka
authors.forename: K
authors.initials: K
authors.lastname: Shii
authors.forename: K
authors.initials: K
authors.lastname: Yokono
authors.forename: N
authors.initials: N
authors.lastname: Mizuno
authors.forename: S
authors.initials: S
authors.lastname: Baba
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D003432:Cross-Linking Reagents; D006150:Guanine Nucleotides / Q000494:pharmacology; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D006624:Hippocampus / Q000378:metabolism; D008623:Mercaptoethanol / Q000494:pharmacology; D008970:Molecular Weight; D009478:Neuropeptide Y / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D019894:Peptide YY; D010455:Peptides / Q000378:metabolism; D017476:Receptors, Neuropeptide Y; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000378:metabolism*; D013388:Succinimides; D013552:Swine; D013873:Thionucleotides / Q000494:pharmacology; D014018:Tissue Distribution
chemical_list: D003432:Cross-Linking Reagents; D006150:Guanine Nucleotides; D009478:Neuropeptide Y; D010446:Peptide Fragments; D010455:Peptides; D017476:Receptors, Neuropeptide Y; D017981:Receptors, Neurotransmitter; D013388:Succinimides; D013873:Thionucleotides; D019894:Peptide YY; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D008623:Mercaptoethanol; D006160:Guanosine Triphosphate; C019358:disuccinimidyl suberate