A comparison of noninternalizing (herkinorin) and internalizing (DAMGO) μ‐opioid agonists on cellular markers related to opioid tolerance and dependence

@article{Xu2007ACO,
  title={A comparison of noninternalizing (herkinorin) and internalizing (DAMGO) $\mu$‐opioid agonists on cellular markers related to opioid tolerance and dependence},
  author={Heng Xu and John S. Partilla and Xiaoying Wang and John M. Rutherford and Kevin J Tidgewell and Thomas E. Prisinzano and Laura M. Bohn and Richard B. Rothman},
  journal={Synapse},
  year={2007},
  volume={61}
}
Previous studies established that Tyr‐D‐Ala‐Gly‐N‐Me‐Phe‐Gly‐ol (DAMGO) and (2S,4aR,6aR,7R,9S,10aS,10bR)‐9‐(Benzoyloxy)‐2‐(3‐furanyl)dodecahydro‐6a,10b‐dimethyl‐4,10‐dioxo‐2H‐naphtho‐[2,1‐c]pyran‐7‐carboxylic acid methyl ester (herkinorin) are fully efficacious μ‐agonists. Herkinorin (HERK), unlike DAMGO, does not recruit β‐arrestin and promote μ‐receptor internalization, even in cells that over express β‐arrestin. We hypothesized that chronic HERK and DAMGO treatment will differentially affect… 
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