The prerequisite for Y2-mediated biological activity was elaborated by synthesizing analogs of neuropeptide Y (NPY) 1-4-Ahx-25-36. The finding, that a pronounced hydrophobic segment is required in the C-terminal segment for signal transduction led to the development of a Y2-selective agonist, which contains cyclohexylalanine at position 30 and/or 31.

A discontinuous 17-amino acid peptide analog of neuropeptide Y (NPY), NPY 1-4-Ahx-25-36 containing 6-aminohexanoic acid instead of the residues 5 to 24, was found to bind preferentially to Y2 subtypes of NPY receptors. In order to further characterize the binding site, three different types of cyclic analogs were synthesized. Firstly lactamisation between residues 2 and 30 led to the most selective Y2-agonist, secondly lactamisation between the N-terminus and residue 31 reduced binding significantly. Thirdly, any cyclization including the C-terminus led to an inactive compound. Circular dichroism revealed different conformations for the three analogs with reduced alpha-helical content in comparison to the linear ana-log. The different conformation of the peptides has been confirmed by molecular dynamics simulations. A model for peptide-receptor interaction is suggested.

The low-molecular-mass, cyclic analog of neuropeptide Y, [Ahx5-24, gamma-Glu2-epsilon-Lys30] NPY (YESK-Ahx-RHYINKITRQRY; Ahx, 6-aminohexanoic acid; NPY, neuropeptide Y), was synthesized and investigated for receptor binding, inhibition of forskolin-stimulated cAMP accumulation, inhibition of electrically stimulated rat vas deferens contractions and ability to increase blood pressure. Like the linear peptide [Ahx5-24] NPY (YPSK-Ahx-RHYINLITRQRY), the more rigid, cyclic analog showed good correlation between receptor binding to rabbit kidney membranes and biological activity in the vas deferens assay. Binding of this peptide to a new Y2-receptor-expressing cell line was slightly reduced, compared to the linear peptide [Ahx5-24] NPY, however inhibition of cAMP accumulation was even more efficient.Unlike the linear peptide [Ahx5-24] NPY, the cyclic analog did not induce a blood pressure increase in rats. Reduced binding to Y1 receptor-expressing SK-N-MC cells, as well as the loss of capability of signal transduction, suggest that only Y2-mediated activity is preserved after cyclization. The selectivity of the cyclic compound for Y2 subtypes of NPY receptors with respect to inhibition of cAMP accumulation is more than fortyfold increased, as compared to the linear NPY-(13-36) peptide, which has been used to determine Y2 selectivity so far.

Conference Article| November 01 1992 Characterization of the binding site of neuropeptide Y to the rabbit kidney receptor using multiple peptide synthesis Annette G. Beck-Sickinger; Annette G. Beck-Sickinger * 1Institute of Organic Chemistry, University of Tübingen, Auf der Morgenstelle 18, D-7400 Tübingen, Germany *To whom correspondence should be addressed. Search for other works by this author on: This Site PubMed Google Scholar Hansjörg Dürr; Hansjörg Dürr 1Institute of Organic Chemistry, University of Tübingen, Auf der Morgenstelle 18, D-7400 Tübingen, Germany Search for other works by this author on: This Site PubMed Google Scholar Eike Hoffmann; Eike Hoffmann 1Institute of Organic Chemistry, University of Tübingen, Auf der Morgenstelle 18, D-7400 Tübingen, Germany Search for other works by this author on: This Site PubMed Google Scholar Wolfram Gaida; Wolfram Gaida †Department of Pharmacology, Boehringer Ingelheim KG, D-6507 Ingelheim, Germany Search for other works by this author on: This Site PubMed Google Scholar Günther Jung Günther Jung 1Institute of Organic Chemistry, University of Tübingen, Auf der Morgenstelle 18, D-7400 Tübingen, Germany Search for other works by this author on: This Site PubMed Google Scholar Biochem Soc Trans (1992) 20 (4): 847–850. https://doi.org/10.1042/bst0200847 Article history Received: May 13 1992 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn Email Cite Icon Cite Get Permissions Citation Annette G. Beck-Sickinger, Hansjörg Dürr, Eike Hoffmann, Wolfram Gaida, Günther Jung; Characterization of the binding site of neuropeptide Y to the rabbit kidney receptor using multiple peptide synthesis. Biochem Soc Trans 1 November 1992; 20 (4): 847–850. doi: https://doi.org/10.1042/bst0200847 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Society Transactions Search Advanced Search © 1992 Biochemical Society1992 Article PDF first page preview Close Modal You do not currently have access to this content.