Data and statistical analysis
IC50 and EC50 values were determined by non-linear regression using GraphPad Prism 8, which was also used for statistical calculation. Sigmoid curves were fitted logistically with a Hill slope of 1 or -1 for the activation and binding curve, respectively.
To calculate the total density of receptors expressed (Bmax) we used equation (1) (Deblasi, Reilly et al. 1989):