Effect of nociceptin/orphanin FQ on venous tone in conscious rats

Aly M. Abdelrahman, Catherine C.Y. Pang

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


Nociceptin (orphanin FQ) is an endogenous agonist for the opioid receptor-like1 (ORL1) receptor. We investigated the effects of nociceptin on mean circulatory filling pressure, an index of venous tone. The effects of nociceptin (10, 30 nmol/kg, i.v.) and the vehicle (0.9% NaCl) on mean arterial pressure, heart rate and mean circulatory filling pressure were examined in two groups each of conscious rats: rats with, or without, ganglionic blockade through pretreatment with mecamylamine (1 mg/kg, i.v.) and noradrenaline (2 μg/kg min, i.v.). In the unblocked rats, both doses of nociceptin decreased mean arterial pressure and heart rate, and the high dose also decreased mean circulatory filling pressure. In the ganglionic-blocked rats, nociceptin did not alter heart rate but caused greater reductions of mean arterial pressure and mean circulatory filling pressure. The vehicle had no effects in any group. Therefore, nociceptin is a depressor agent with prominent direct venodilator and bradycardic action.

Original languageEnglish
Pages (from-to)143-147
Number of pages5
JournalEuropean Journal of Pharmacology
Issue number2-3
Publication statusPublished - Nov 29 2002
Externally publishedYes


  • Arterial pressure
  • Capacitance vessel
  • Circulatory filling pressure
  • Ganglionic blockade
  • Mean
  • Nociceptin
  • ORL1 receptor
  • Venous tone

ASJC Scopus subject areas

  • Pharmacology


Dive into the research topics of 'Effect of nociceptin/orphanin FQ on venous tone in conscious rats'. Together they form a unique fingerprint.

Cite this