[Nphe1]nociceptin(1-13)-NH2 antagonizes nociceptin-induced hypotension, bradycardia, and hindquarters vasodilation in the anesthetized rat

Can J Physiol Pharmacol. 2002 Jan;80(1):31-5. doi: 10.1139/y02-003.

Abstract

The purpose of this study was to investigate the effects of [Nphe1]nociceptin(1-13)-NH2 on nociceptin-induced decreases in mean arterial pressure (MAP), heart rate (HR), and hindquarters vascular bed resistance (HVBR) of the anesthetized rat. The results showed that i.c.v. or i.v. [Nphe1]nociceptin(1-13)-NH2 (1.5-12 nmol/kg and 5-120 nmol/kg, respectively) could antagonize the depressor effects of i.c.v. or i.v. nociceptin (3 and 30 nmol/kg, respectively) on MAP and HR. Furthermore, [Nphe1]nociceptin(1-13)-NH2 (5-120 nmol/kg) could reverse nociceptin (30 nmol/kg)-induced decrease of HVBR. However, [Nphe1]nociceptin(1-13)-NH2 had no significant effects on similar effects induced by morphine. Our results suggest that [Nphe1]nociceptin(1-13)-NH2 acts as a selective antagonist of the nociceptin receptor in the cardiovascular system of the rat.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anesthesia*
  • Animals
  • Blood Pressure / drug effects*
  • Dose-Response Relationship, Drug
  • Female
  • Heart Rate / drug effects*
  • Hindlimb / blood supply
  • Injections, Intravenous
  • Injections, Intraventricular
  • Male
  • Morphine / antagonists & inhibitors
  • Morphine / pharmacology
  • Naloxone / pharmacology
  • Narcotic Antagonists / pharmacology
  • Narcotics / pharmacology
  • Nociceptin
  • Opioid Peptides / antagonists & inhibitors*
  • Opioid Peptides / therapeutic use*
  • Peptide Fragments / therapeutic use*
  • Rats
  • Rats, Wistar
  • Regional Blood Flow / drug effects
  • Vascular Resistance / drug effects
  • Vasodilation / drug effects*
  • Vasodilator Agents / antagonists & inhibitors*

Substances

  • Narcotic Antagonists
  • Narcotics
  • Opioid Peptides
  • Peptide Fragments
  • Vasodilator Agents
  • nociceptin-(1-13)-NH2, NPhe(1)-
  • Naloxone
  • Morphine