Fig. 3.
Ghrelin does not alter the EMAX of MK-677, GHRP-6, or L-692,585 to activate Gαo1 via the ghrelin receptor; [35S]GTPγS binding experiments were performed on membranes of HEK293 cells transfected to coexpress Gαo1 and the ghrelin receptor. Data points represent the mean ± S.E.M of three independent experiments performed in triplicate. Data were fitted to eq. 2. Data are shown fitted with αβ = 0 and the slope transducer function constrained to 1. A, A series of concentration-response curves to MK-677 was performed in the absence (control) or presence of varying concentrations of ghrelin (as indicated). B, equivalent studies were performed with GHRP-6 and varying concentrations of ghrelin. C, equivalent studies were performed with L-692,585 and varying concentrations of ghrelin.