Fig. 4

Application of Amylin to Xenopus laevis oocytes expressing AMY₁-R caused concentration-dependent increase in current at a holding potential of − 70 mV. In CTR expressing oocytes a significant response was obtained at 1 μM amylin. Amylin had no effect on oocytes expressing CGRP-R, RAMP1, CLR or non-injected oocytes (control). Curves fittings by non-linear regression curves using least square non-lin fit of the c-r relationship of log(agonist) vs. response (three parameters) were performed. The top and the bottom of the AMY₁-R curve was constrained to the maximum response of amylin and zero, respectively. Furthermore, the response to 10 μM of amylin at the AMY₁-R was not included in the calculation of the non-linear regression curve. Statistical evaluation was performed by ordinary One-way ANOVA followed by Dunnet’s multiple comparisons test on the response to the different concentrations of Amylin at one receptor at the time as compared to the 1 μM amylin response in non-injected control oocytes* p < 0.05; **p < 0.01. Mann Whitney test was used for the comparison of Amylin 1 μM on CTR, as compared to its response in non-injected control oocytes ### p = 0.0010. The number of experiments performed at each data point is between 2 and 26. Each curve-fitting relies on experiments performed on 13 non-injected oocytes, and 13, 47, 7 and 7 oocytes expressing CGRP-R, AMY₁-R, RAMP1 and CLR, respectively. The one point for CTR consists of experiments performed on 5 oocytes