Figure. Concentration-dependent activation of NPFFR2 by NPFF. Reporter cells were transfected with the expression plasmid for neuro­pep­tide FF receptor 2 (NPFFR2) and treated with various concentrations of neuro­pep­tide FF (NPFF). Data points shown are the mean ± SEM of an experiment performed in triplicate, and the curve is a fit to Hill equation with an EC50 of 280 pM.