Morphine Desensitization, Internalization, and Down-Regulation of the μ Opioid Receptor Is Facilitated by Serotonin 5-Hydroxytryptamine2A Receptor Coactivation

@article{LpezGimnez2008MorphineDI,
  title={Morphine Desensitization, Internalization, and Down-Regulation of the $\mu$ Opioid Receptor Is Facilitated by Serotonin 5-Hydroxytryptamine2A Receptor Coactivation},
  author={Juan F. L{\'o}pez-Gim{\'e}nez and Maria Teresa Vilar{\'o} and Graeme Milligan},
  journal={Molecular Pharmacology},
  year={2008},
  volume={74},
  pages={1278 - 1291}
}
Analysis of the distribution of mRNA encoding the serotonin (5-hydroxytryptamine) 5-HT2A receptor and the μ opioid peptide receptor in rat brain demonstrated their coexpression in neurons in several distinct regions. These regions included the periaqueductal gray, an area that plays an important role in morphine-induced analgesia but also in the development of tolerance to morphine. To explore potential cross-regulation between these G protein-coupled receptors, the human μ opioid peptide… 

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