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Updated: Jul 28, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
Agonists and antagonists of adenosine receptors and morphine withdrawal syndrome in rats
1Department of Pharmacodynamics, Medical Academy, Lublin, Poland.
Abstract:
The compounds activating adenosine system alleviated morphine withdrawal syndrome (the number of escape attempts and body shakes) in rats. Body shakes were decreased mostly by N-ethylcarboxamidoadenosine, cyclohexyladenosine, dipyridamole and 2-chloroadenosine, while R-phenylisopropyladenosine very strongly decreased the number of escape attempts. Adenosine receptor antagonists (caffeine and theophylline) increased the number of escape attempts in morphine-dependent rats. Caffeine (10 mg/kg), administered preventively, antagonized the inhibitory effects of adenosine analogs. These results suggest the existence of relation between opioid receptors and the adenosine system.
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