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Updated: Jul 27, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
Opiate receptors and endogenous opioid peptides in tolerance and dependence
Abstract:
The impact of the discovery of the endogenous opioid peptides, the enkephalins and endorphins, on our concepts of the mechanisms of tolerance to, and dependence on, opiates is discussed. After a brief survey of the chemistry of the opioid peptides, the possibility of an interaction between opiates and the peptides is considered and a hypothesis formulated. Experimental proof is presented as far as it has become available. The possible mechanisms involved in the development of tolerance and dependence for alcohol, barbiturates and opiates are compared briefly.
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