Cross tolerance between morphine and the long-term analgesic reaction to inescapable shock. Academic Article uri icon

Overview

abstract

  • Animals exposed to a variety of stressors display a temporary analgesic reaction. This short-term analgesia has been shown to be reversible by opiate antagonists and cross-tolerant with morphine following some stress conditions, but not following others. It has recently been shown that inescapable shock parameters which produce behavioral '"learned helplessness" effects also produce a short-term analgesic reaction, and that this reaction can be re-aroused by a brief exposure to shock 24 hours later. Further, both the immediate and long-term antinociceptive reaction which follow shocks of this type have been shown to be reversible by opiate antagonists. Here it is shown that the long-term analgesic reaction is completely cross tolerant with morphine. Implications of these results for opioid mediation of learned helplessness and opioid versus nonopioid mediation of stress-induced analgesia are discussed.

publication date

  • May 1, 1981

Research

keywords

  • Morphine
  • Pain

Identity

Scopus Document Identifier

  • 0019434961

Digital Object Identifier (DOI)

  • 10.1016/0091-3057(81)90130-1

PubMed ID

  • 7243845

Additional Document Info

volume

  • 14

issue

  • 5