Figure 5.

Concentration-response curves for GIRK1/GIRK2 channel activation by increasing concentrations of DAMGO (A), fentanyl (B), morphine (C), M3G (D) and M6G (E). Agonist-gated currents were evoked from Xenopus laevis oocytes coexpressing GIRK1/GIRK2 and RGS4 with hMORwt, hMORN230L or hMORN230T. The agonist-gated increase of GIRK current at each concentration was normalized to a maximal response of 100%. Each point represents the average current activation evoked from 5 to 8 oocytes (mean±s.e.mean).