Summary of biased agonism among several different μOR agonists with regard to different cellular responses

Relative efficacy ratios were extracted from quantitative studies in HEK-293 cells.

[35S]GTPγS binding+++a,b+++a,c+++a+++a,c+++a,c+++b
ERK1/2 phosphorylation+++d+++dN.D.N.D.N.D.+++d
μOR phosphorylation+++a,d,e+a,d,e,f+++a+++a+++a,f+e
β-Arrestin2 recruitment+++a+a,c+++a++a,c+++a,ce
μOR internalization+++a,e+a+++a++a+++ae
  • N.D., not determined.

  • a McPherson et al., 2010.

  • b Xu et al., 2007.

  • c Molinari et al., 2010.

  • d Schulz et al., 2004.

  • e Groer et al., 2007.

  • f Zhang et al., 1998.