Functional Selectivity and Classical Concepts of Quantitative Pharmacology

  title={Functional Selectivity and Classical Concepts of Quantitative Pharmacology},
  author={Jonathan D. Urban and William P Clarke and Mark von Zastrow and David E. Nichols and Brian K. Kobilka and Harel Weinstein and Jonathan A. Javitch and Bryan L. Roth and Arthur Christopoulos and Patrick M. Sexton and Keith J. Miller and Michael Spedding and Richard B. Mailman},
  journal={Journal of Pharmacology and Experimental Therapeutics},
  pages={1 - 13}
The concept of intrinsic efficacy has been enshrined in pharmacology for half of a century, yet recent data have revealed that many ligands can differentially activate signaling pathways mediated via a single G protein-coupled receptor in a manner that challenges the traditional definition of intrinsic efficacy. Some terms for this phenomenon include functional selectivity, agonist-directed trafficking, and biased agonism. At the extreme, functionally selective ligands may be both agonists and… 

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