Anti-allodynic and anti-hyperalgesic effects of nociceptin receptor antagonist, JTC-801, in rats after spinal nerve injury and inflammation.

Abstract

The effects of nociceptin/orphanin FQ (N/OFQ) peptide receptor antagonist JTC-801 on allodynia and hyperalgesia were examined in rats in order to explore the involvement of N/OFQ system in these pathological pain states. Tactile allodynia induced by L5/L6 spinal nerve ligation was reversed by both systemic (3-30 mg/kg) and spinal (22.5 and 45 pg) JTC-801 in a dose-dependent manner. Concerning hyperalgesia induced by formalin injection into the hindpaw, JTC-801 dose-dependently suppressed the second phase, but not the first phase, of the licking behavior. Furthermore, systemic JTC-801 reduced Fos-like immunoreactivity in the dorsal horn of the spinal cord (laminae I/II). In conclusion, N/OFQ receptor antagonist JTC-801 exerted anti-allodynic and anti-hyperalgesic effects in rats, suggesting that N/OFQ system might be involved in the modulation of neuropathic pain and inflammatory hyperalgesia.

• Authors: Hisayoshi Tamai, Shigehito Sawamura, Kenji Takeda, Ryo Orii, Kazuo Hanaoka
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 510 Issue 3 Pg. 223-8 (Mar 14 2005) ISSN: 0014-2999 [Print] Netherlands
• PMID: 15763246 (Publication Type: Journal Article)

Chemical References

• Aminoquinolines
• Benzamides
• N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide
• Narcotic Antagonists
• Proto-Oncogene Proteins c-fos
• Receptors, Opioid
• Nociceptin Receptor
• Oprl protein, rat

Topics

• Aminoquinolines (pharmacology)
• Animals
• Benzamides (pharmacology)
• Hyperalgesia (physiopathology, prevention & control)
• Hyperesthesia (physiopathology, prevention & control)
• Male
• Narcotic Antagonists
• Neuritis (physiopathology, prevention & control)
• Pain Measurement
• Proto-Oncogene Proteins c-fos (metabolism)
• Rats
• Rats, Sprague-Dawley
• Receptors, Opioid
• Spinal Nerves (drug effects, injuries, physiopathology)
• Touch
• Nociceptin Receptor