The role of mu- and kappa-opioid receptors in cocaine-induced conditioned place preference

Jpn J Pharmacol. 1992 Apr;58(4):435-42. doi: 10.1254/jjp.58.435.


Effects of buprenorphine, U-50,488H, naltrexone and lithium chloride on cocaine conditioned place preference were examined. Buprenorphine, a mixed opioid agonist-antagonist, blocked the cocaine-induced place preference. Furthermore, the kappa-receptor agonist U-50,488H and the mu-receptor antagonist naltrexone both antagonized the cocaine preference. U-50,488H or naltrexone alone induced a place aversion in a dose-dependent manner. However, the cocaine-induced conditioned place preference was not blocked by lithium chloride, although the latter induced a conditioned place aversion, indicating that the antagonism of cocaine-induced place preference by U-50,488H or naltrexone does not result from a functional antagonism. These results suggest that mu- and kappa-opioid receptors may be involved in cocaine-induced conditioned place preference.

MeSH terms

  • 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer
  • Animals
  • Buprenorphine / pharmacology
  • Chlorides / pharmacology
  • Cocaine / pharmacology*
  • Conditioning, Psychological / drug effects*
  • Lithium / pharmacology
  • Lithium Chloride
  • Male
  • Naltrexone / pharmacology
  • Pyrrolidines / pharmacology
  • Rats
  • Rats, Inbred Strains
  • Receptors, Opioid, kappa / drug effects
  • Receptors, Opioid, kappa / physiology*
  • Receptors, Opioid, mu / drug effects
  • Receptors, Opioid, mu / physiology*


  • Chlorides
  • Pyrrolidines
  • Receptors, Opioid, kappa
  • Receptors, Opioid, mu
  • Buprenorphine
  • Naltrexone
  • 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer
  • Lithium
  • Lithium Chloride
  • Cocaine