Inbred strain differences in morphine-induced analgesia with the hot plate assay: A reassessment

J. K. Belknap, M. Lamé, P. W. Danielson

Research output: Contribution to journalArticlepeer-review

30 Scopus citations


Using the hot plate assay of analgesia, several investigators have reported DBA/2J mice to be much more sensitive to morphine and other opioids than C57BL/6J mice using paw-lick as the behavioral end point. In the present studies, we compared DBA/2J, C57BL/6J, and C3H/HeJ mice on two behavioral end points, either (1) the initial response to the hot plate, either a hind paw-lift, paw-shake, or paw-lick, whichever occurred first, or (2) the paw-lick response. In response to either morphine or saline, all three strains showed roughly equivalent latencies to the initial response, but the DBA/2J strain was markedly slow to show paw-lick as a nocifensive response compared to the C57BL/6J strain. As a result, only for the paw-lick response were there significant differences among the three inbred strains in morphine analgesia. Thus, differences in analgesic sensitivity among these strains are largely a function of the behavioral end point used to assess nociception to the hot plate.

Original languageEnglish (US)
Pages (from-to)333-338
Number of pages6
JournalBehavior genetics
Issue number2
StatePublished - Mar 1990
Externally publishedYes


  • C3H/HeJ
  • C57BL/6J
  • DBA/2J
  • analgesia
  • genetics
  • hot plate assay
  • morphine
  • opioid

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Genetics
  • Genetics(clinical)


Dive into the research topics of 'Inbred strain differences in morphine-induced analgesia with the hot plate assay: A reassessment'. Together they form a unique fingerprint.

Cite this