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Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
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Analgesic tolerance to morphine is regulated by PPARγ.
Giordano de Guglielmo1, Marsida Kallupi, Giulia Scuppa
1School of Pharmacy, Pharmacology Unit, University of Camerino, Camerino, Italy.
British Journal of Pharmacology
|July 23, 2014
Summary
Peroxisome proliferator-activated receptor gamma (PPARγ) activation attenuates morphine tolerance. Pharmacological activation of PPARγ may reduce opioid tolerance and abuse potential.
Area of Science:
- Neuroscience
- Pharmacology
- Molecular Biology
Background:
- Chronic opioid use causes analgesic tolerance and side effects like addiction.
- Investigating molecular mechanisms underlying opioid tolerance is crucial for developing safer analgesics.
Purpose of the Study:
- To investigate the role of Peroxisome proliferator-activated receptor gamma (PPARγ) in the development of morphine analgesic tolerance in mice.
Main Methods:
- Morphine analgesia was assessed using the tail immersion test in mice.
- PPARγ activation was achieved using pioglitazone, and antagonism using GW-9662.
- Conditional neuronal PPARγ knockout (KO) mice were used to study its specific role.
Main Results:
- Daily morphine administration rapidly induced tolerance to analgesia.
- Co-administration of pioglitazone attenuated morphine tolerance, an effect blocked by GW-9662.
- Neuronal PPARγ KO mice exhibited accelerated and more pronounced morphine tolerance.
Conclusions:
- PPARγ plays a significant role in modulating morphine tolerance.
- Pharmacological activation of PPARγ may reduce the development of opioid tolerance.
- Targeting neuronal PPARγ could offer strategies to mitigate opioid abuse and tolerance.
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