Levorphanol and swim stress-induced analgesia in selectively bred mice: evidence for genetic commonalities

Przemyslaw Marek, Jeffrey S. Mogil, John Belknap, Bogdan Sadowski, John C. Liebeskind

Research output: Contribution to journalArticle

25 Scopus citations


Two independent selective breeding programs have developed divergent lines of mice expressing either high and low swim stress-induced analgesia (HA/LA lines; Jastrzebiec, Poland) or high and low levorphanol analgesia (HAR/LAR lines; Portland, OR). In the present study, mice from both programs were tested for both levorphanol analgesia (2 mg/kg) and an opioid-mediated swim stress-induced analgesia (3 min swimming in 32°C water) in the hot-plate test. Mice selected for high and low levorphanol analgesia displayed high and low swim stress-induced analgesia, respectively; mice selected for high and low swim stress-induced analgesia displayed high and low levorphanol analgesia, respectively. This pattern of correlated responses suggests a high degree of common genetic determination in opiate and swim stress-induced analgesia. These findings also suggest that individual differences in analgesic responsiveness to opiate drugs result from genetically determined individual differences in endogenous pain inhibitory mechanisms.

Original languageEnglish (US)
Pages (from-to)353-357
Number of pages5
JournalBrain Research
Issue number2
Publication statusPublished - Apr 16 1993
Externally publishedYes



  • Genetics
  • Levorphanol
  • Opiate
  • Opioid
  • Selective breeding
  • Stress-induced analgesia

ASJC Scopus subject areas

  • Developmental Biology
  • Molecular Biology
  • Clinical Neurology
  • Neuroscience(all)

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