Oxytocin blocks the development of heroin-fentanyl cross-tolerance in mice

Márta Kriván, Gyula Szabó, Zoltán Sarnyai, Gábor L. Kovács, Gyula Telegdy

Research output: Contribution to journalArticle

8 Citations (Scopus)


The development of cross-tolerance to an analgesic effect was observed between two μ-receptor agonists, heroin and fentanyl. Repeated treatments with heroin twice a day for 4 days resulted in a decreased nociceptive effect to fentanyl on day 5. The fentanyl dose-response line shifted to the right, and was considered to be a sign of the development of cross-tolerance. Peripheral treatment with oxytocin did not block the development of heroin-fentanyl cross-tolerance. However, intracerebroventricular administration of oxytocin blocked the development of tolerance, causing a leftward shift in the dose-response curve and supporting the assumption that oxytocin blocks the development of heroin-fentanyl cross-tolerance via CNS mechanisms.

Original languageEnglish
Pages (from-to)591-594
Number of pages4
JournalPharmacology, Biochemistry and Behavior
Issue number3
Publication statusPublished - Nov 1995



  • Analgesic effect
  • Cross-tolerance
  • Fentanyl
  • Heroin
  • Mice
  • Narcotics
  • Opiates
  • Oxytocin

ASJC Scopus subject areas

  • Biochemistry
  • Toxicology
  • Pharmacology
  • Clinical Biochemistry
  • Biological Psychiatry
  • Behavioral Neuroscience

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