Characterisation of a new chimeric ligand for galanin receptors: galanin(1-13)-[D-Trp(32)]-neuropeptide Y(25-36)amide

Regul Pept. 2001 Oct 15;102(1):15-9. doi: 10.1016/s0167-0115(01)00298-1.

Abstract

In this work, we studied a novel chimeric peptide, M242, galanin(1-13)-[D-Trp(32)]-neuropeptide Y(25-36)amide, and examined its properties in comparison with its parent peptide, M32, galanin(1-13)-neuropeptide Y(25-36)amide, a previously known high-affinity ligand for galanin receptors, and galanin itself. Binding assays performed in Bowes cells known to express human galanin receptor type 1 (hGalR1) and in Chinese hamster ovary cells overexpressing human galanin receptor type 2 (hGalR2) revealed that all three ligands had comparable affinities: at hGalR1<1 nM and at hGalR2<10 nM. However, in rat hippocampal membranes M242 had a 24-fold lower affinity than galanin (9.4 vs. 0.4 nM) and 134-fold lower affinity than M32 (9.4 vs. 0.07 nM). In the same tissue, we also examined the effects of these peptides on adenylate cyclase activity. M32 showed a weak antagonistic behaviour but M242 acted as a potent biphasic regulator of adenylate cyclase. In conclusion, we present and characterise a new peptide M242, which could be a useful tool in studies of galaninergic signalling.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenylyl Cyclases / metabolism
  • Animals
  • CHO Cells
  • Cricetinae
  • Galanin / antagonists & inhibitors
  • Galanin / chemistry*
  • Galanin / metabolism
  • Hippocampus / metabolism
  • Humans
  • Ligands
  • Neuropeptide Y / analogs & derivatives*
  • Neuropeptide Y / antagonists & inhibitors
  • Neuropeptide Y / chemistry*
  • Neuropeptide Y / metabolism
  • Peptide Fragments / antagonists & inhibitors
  • Peptide Fragments / chemistry*
  • Peptide Fragments / metabolism
  • Protein Binding
  • Rats
  • Receptor, Galanin, Type 1
  • Receptor, Galanin, Type 2
  • Receptors, Galanin
  • Receptors, Neuropeptide / metabolism*
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / metabolism

Substances

  • Ligands
  • Neuropeptide Y
  • Peptide Fragments
  • Receptor, Galanin, Type 1
  • Receptor, Galanin, Type 2
  • Receptors, Galanin
  • Receptors, Neuropeptide
  • Recombinant Fusion Proteins
  • galanin-NPY chimeric peptide M32
  • Galanin
  • Adenylyl Cyclases