Further be differentiated by the long-term fate of the internalized receptors. Although some internalization effects result in rapid recycling of the receptor back to the surface of the cell, other ligands induce much longer term removal and destruction of the receptor from the cell surface (i.e., Mack et al., 1998; Ryman-Rasmussen et al., 2007). Thus, biased agonists produce one or more of these