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Updated: Aug 19, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
[Effect of psychodrugs on morphine effectivity (author's transl)]
Abstract:
After withdrawal of daily treatment with haloperidole (2 mg/kg s.c.) and apomorphine (10 mg/kg s.c.) for 21 days, respectively, and clomipramine (15 mg/kg s.c.) for 28 days, a decrease of morphine analgesia is observed. The findings are interpreted as a sensitivity change of the transmission systems involved in the action mechanism of the antinocifensive morphine effect. Morphine lethality remains unaffected by the synaptic efficiency of the transmission systems investigated.
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