The Analgesic Effects of Supraspinal μ and δ Opioid Receptor Agonists Are Potentiated during Persistent Inflammation

  title={The Analgesic Effects of Supraspinal $\mu$ and $\delta$ Opioid Receptor Agonists Are Potentiated during Persistent Inflammation},
  author={R. Hurley and Donna L. Hammond},
  journal={The Journal of Neuroscience},
  pages={1249 - 1259}
This study examined the antihyperalgesic and antinociceptive effects of opioid receptor agonists microinjected in the rostral ventromedial medulla (RVM) of rats 4 hr, 4 d, and 2 weeks after the induction of an inflammatory injury by injection of complete Freund's adjuvant (CFA) in one hindpaw. Nociceptive sensitivity of the ipsilateral, inflamed and the contralateral, uninflamed hindpaws was determined by the radiant-heat paw withdrawal test. The antihyperalgesic potency of the μ opioid… 

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