[Phe1psi(CH2-NH)Gly2]-nociceptin-(1-13)NH2, a proposed antagonist of the nociceptin receptor, is a potent and stable agonist in the rat spinal cord

Neurosci Lett. 1998 Jun 19;249(2-3):127-30. doi: 10.1016/s0304-3940(98)00411-x.

Abstract

[Phe1psi(CH2-NH)Gly2]-nociceptin-(1-13)NH2 is an nociceptin analogue which has been shown to be a selective antagonist of the nociceptin receptor in peripheral tissues. We now report that intrathecal [Phe1psi(CH2-NH)Gly2]-nociceptin-(1-13)NH2 produced a dose-dependent depression of the nociceptive flexor reflex in rats, an effect that is similar to nociceptin. The duration of depression produced by [Phe1psi(CH2-NH)Gly2]-nociceptin-(1-13)NH2 was significantly more prolonged than by nociceptin. The reflex depressive effect of nociceptin was not blocked by [Phe1psi(CH2-NH)Gly2]-nociceptin-(1-13)NH2. The results indicated that the proposed nociceptin receptor antagonist [Phe1psi(CH2-NH)Gly2]-nociceptin-(1-13)NH2 is a potent agonist in rat spinal cord and more resistant to enzymatic degradation compared to nociceptin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dose-Response Relationship, Drug
  • Female
  • Injections, Spinal
  • Narcotic Antagonists*
  • Nociceptin
  • Nociceptin Receptor
  • Opioid Peptides / administration & dosage
  • Opioid Peptides / pharmacology*
  • Peptide Fragments / administration & dosage
  • Peptide Fragments / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Opioid / agonists*
  • Reflex / drug effects*
  • Spinal Cord / drug effects*
  • Time Factors

Substances

  • Narcotic Antagonists
  • Opioid Peptides
  • Peptide Fragments
  • Receptors, Opioid
  • nociceptin (1-13)-NH2, Phe(1)-psi(CH2-NH)-Gly(2)-
  • Nociceptin Receptor
  • Oprl protein, rat