Figure. Concentration-dependent activation of P2RY11 by ATP. Reporter cells were transfected with either the expression plasmid for purin­ergic receptor P2Y11 (P2RY11) or the mock plasmid and treated with various concentrations of adeno­sine tri­phos­phate (ATP). 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 13 µM.