Fig. 4.
Arrestin recruitment assay: (A) 2AG (▪) and the stable anandamide analog, methanandamide (▲), failed to recruit arrestins. (B) The natural product, 4-O-methylhonokiol (▪) (EC50 51 nM), was a low efficacy agonist, while β caryophyllene (▲) failed to recruit arrestins. (C) SR144528 (▼) (EC50 2.5 nM) was an inverse agonist, while AM630 (▪) and JTE907 (▲) were low efficacy agonists in recruiting arrestins. EC50 and Emax values were obtained by fitting the dose-response curve using nonlinear regression with GraphPad Prism 4.0. Data represent mean ± S.E.M. of at least three experiments.