Structure-activity relationship studies of spinorphin as a potent and selective human P2X(3) receptor antagonist

J Med Chem. 2007 Sep 6;50(18):4543-7. doi: 10.1021/jm070114m. Epub 2007 Aug 3.

Abstract

Spinorphin, an endogenous antinociceptive peptide (LVVYPWT), showed potent and non-competitive antagonism at the ATP-activated human P2X3 receptor (IC50 = 8.3 pM) in a two-electrode voltage clamp assay with recombinant human P2X3 receptors expressed in Xenopus oocytes. Single alanine substitutions from 1st to 4th amino acids and the cyclic form of LVVYPWT sustained antagonistic properties at the human P2X3 receptors, whereas the threonine to alanine substitution resulted in an enhancing effect of the agonistic activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Female
  • Humans
  • Mice
  • Oligopeptides / chemical synthesis*
  • Oligopeptides / chemistry
  • Oligopeptides / pharmacology
  • Oocytes / drug effects
  • Oocytes / physiology
  • Patch-Clamp Techniques
  • Purinergic P2 Receptor Antagonists*
  • Receptors, Purinergic P2X
  • Receptors, Purinergic P2X3
  • Recombinant Proteins / antagonists & inhibitors
  • Structure-Activity Relationship
  • Xenopus

Substances

  • Oligopeptides
  • P2RX3 protein, human
  • P2rx3 protein, mouse
  • Purinergic P2 Receptor Antagonists
  • Receptors, Purinergic P2X
  • Receptors, Purinergic P2X3
  • Recombinant Proteins
  • spinorphin