Engineering galanin analogues that discriminate between GalR1 and GalR2 receptor subtypes and exhibit anticonvulsant activity following systemic delivery

J Med Chem. 2010 Feb 25;53(4):1871-5. doi: 10.1021/jm9018349.

Abstract

Galanin modulates seizures in the brain through two galanin receptor subtypes, GalR1 and GalR2. To generate systemically active galanin receptor ligands that discriminate between GalR1 and GalR2, the GalR1-preferring analogue Gal-B2 (or NAX 5055) was rationally redesigned to yield GalR2-preferring analogues. Systematic truncations of the N-terminal backbone led to [N-Me,des-Sar]Gal-B2, containing N-methyltryptophan. This analogue exhibited 18-fold preference in binding toward GalR2, maintained agonist activity, and exhibited potent anticonvulsant activity in mice following intraperitoneal administration.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Anticonvulsants / chemical synthesis*
  • Anticonvulsants / chemistry
  • Anticonvulsants / pharmacology
  • Calcium / metabolism
  • Galanin / analogs & derivatives*
  • Galanin / chemical synthesis*
  • Galanin / chemistry
  • Galanin / pharmacology
  • Humans
  • In Vitro Techniques
  • Ligands
  • Mice
  • Molecular Sequence Data
  • Oligopeptides / chemical synthesis*
  • Oligopeptides / chemistry
  • Oligopeptides / pharmacology
  • Radioligand Assay
  • Rats
  • Receptor, Galanin, Type 1 / agonists
  • Receptor, Galanin, Type 1 / metabolism*
  • Receptor, Galanin, Type 2 / agonists
  • Receptor, Galanin, Type 2 / metabolism*
  • Structure-Activity Relationship

Substances

  • Anticonvulsants
  • Ligands
  • Oligopeptides
  • Receptor, Galanin, Type 1
  • Receptor, Galanin, Type 2
  • Galanin
  • Calcium