Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities

We describe a protocol to examine the development of opioid-induced hyperalgesia and tolerance in mice. Based on the measurement of thermal and mechanical nociceptive responses of naïve and morphine-treated animals, it allows to quantify the increase in pain sensitivity (hyperalgesia) and decrease in analgesia (tolerance) associated with chronic opiate administration.