Peripheral opioids act as analgesics in bone cancer pain in mice.

Abstract

Previous reports have shown that systemic administration of morphine can prevent the thermal hyperalgesia induced by the development of an osteosarcoma in C3H/HeJ mice after the implantation of NCTC 2472 cells. We show here that this type of hyperalgesia is also abolished by the local administration of morphine given at low doses (10 nmol), or the peripheral acting opioid receptor agonist loperamide (146 nmol). The analgesic effect of loperamide is prevented by the administration of the opioid receptor antagonist naloxone methiodide (10 mg/kg, i.p.), which is unable to cross the blood-brain barrier. These results provide evidence which supports the fact that peripheral opioids could be useful tools in the management of some types of cancer pain.

• Authors: Luis Menéndez, Ana Lastra, Agustín Hidalgo, Alvaro Meana, Eva García, Ana Baamonde
• Journal: Neuroreport (Neuroreport) Vol. 14 Issue 6 Pg. 867-9 (May 06 2003) ISSN: 0959-4965 [Print] England
• PMID: 12858049 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Analgesics, Opioid
• Narcotic Antagonists
• Quaternary Ammonium Compounds
• Naloxone
• Loperamide
• N-methylnaloxone
• Morphine

Topics

• Analgesics, Opioid (pharmacology, therapeutic use)
• Animals
• Bone Neoplasms (complications)
• Cell Culture Techniques
• Hyperalgesia (drug therapy, etiology)
• Loperamide (pharmacology)
• Mice
• Mice, Inbred C3H
• Morphine (pharmacology)
• Naloxone (analogs & derivatives, pharmacology)
• Narcotic Antagonists (pharmacology)
• Osteosarcoma (complications)
• Pain (drug therapy, etiology)
• Quaternary Ammonium Compounds