Contralateral, ipsilateral and bilateral treatments with the kappa-opioid receptor agonist U-50,488H in mononeuropathic rats.

Abstract

The effect of repeated contralateral administration of the kappa-opioid receptor agonist U-50,488H (trans-(+/-)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]-benzeneacetamide methanesulfonate) on nociceptive behaviour was investigated and compared with ipsilateral and bilateral treatments in a rat model of peripheral unilateral neuropathy (chronic constriction of the common sciatic nerve). Administration of 0.3 mg U-50,488H into the contralateral hindpaw on days 6 and 10 after induction of mononeuropathy increased hindpaw withdrawal latency to mechanical but not to thermal stimulation compared to saline-treated rats. No difference in pain-related behaviour was found between different peripheral (contralateral, ipsilateral and bilateral) treatments with 0.3 mg U-50,488H. Autotomy behaviour was reduced for 6 weeks after sciatic nerve ligation in rats treated contralaterally with the opioid receptor agonist. Antinociceptive effects of contralaterally administered U-50,488H were abolished by the peripherally acting opioid receptor antagonist naloxone methiodide. Our findings indicate that contralateral treatment with U-50,488H attenuates nociceptive behaviour in mononeuropathic rats. These antinociceptive effects are mediated via peripheral opioid receptors.

• Authors: Indre Bileviciute-Ljungar, Mariana Spetea
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 494 Issue 2-3 Pg. 139-46 (Jun 28 2004) ISSN: 0014-2999 [Print] Netherlands
• PMID: 15212967 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Analgesics, Non-Narcotic
• Receptors, Opioid, kappa
• 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer

Topics

• 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer (administration & dosage, therapeutic use)
• Analgesics, Non-Narcotic (administration & dosage, therapeutic use)
• Animals
• Behavior, Animal (drug effects)
• Constriction, Pathologic
• Functional Laterality (physiology)
• Hot Temperature
• Male
• Pain (psychology)
• Peripheral Nervous System Diseases (drug therapy, pathology)
• Physical Stimulation
• Rats
• Rats, Sprague-Dawley
• Receptors, Opioid, kappa (agonists)
• Sciatic Nerve (pathology)
• Self Mutilation (psychology)