Uncompetitive NMDA receptor antagonists potentiate morphine antinociception recorded from the tail but not from the hind paw in rats

Ewa Kozela, Wojciech Danysz, Piotr Popik*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

47 Scopus citations

Abstract

We investigated the effects of pretreatment with low-affinity, uncompetitive NMDA receptor antagonists on morphine-induced antinociception in rats using the same intensity of thermal stimulus applied to the tail and the paws. Similar baseline responses to thermal stimuli of the same intensity were recorded from tails and hind paws. However, morphine produced equal antinociception from the tail and hind paw when used at doses of 2.5 and 6 mg/kg, respectively. These doses were used in further experiments. Thirty minutes before morphine, rats were administered the NMDA receptor antagonists dextromethorphan (2.5-30 mg/kg), memantine (2.5-15 mg/kg) and MRZ 2/579 (1-amino-1,3,3,5,5-pentamethyl-cyclohexane HCl) (1.25-10 mg/kg). All three compounds significantly and dose-dependently potentiated morphine-induced antinociception recorded from the tail. However, none of these NMDA receptor antagonists affected morphine antinociception recorded from the paw. These findings suggest that low-affinity NMDA receptor antagonists modulate differently morphine antinociceptive activity recorded from the tail and hind paws.

Original languageEnglish
Pages (from-to)17-26
Number of pages10
JournalEuropean Journal of Pharmacology
Volume423
Issue number1
DOIs
StatePublished - 29 Jun 2001
Externally publishedYes

Bibliographical note

Funding Information:
This study was supported by KBN grant No. P05A 04217.

Keywords

  • Antinociception
  • Dextromethorphan
  • Memantine
  • Morphine
  • NMDA receptor antagonist
  • Opiate

Fingerprint

Dive into the research topics of 'Uncompetitive NMDA receptor antagonists potentiate morphine antinociception recorded from the tail but not from the hind paw in rats'. Together they form a unique fingerprint.

Cite this