Inhibition of Na,K-ATPase activity of bovine NPE cells by DcB. Inhibition of Na,K-ATPase activity in NPE cells by DcB was fitted to the two sites model [VCG/V0 = Aα2 * Ki2/([CG] + Ki2) + Aα1 * Ki1/([CG] + Ki1), where A and Ki represent the amplitudes and Ki values for α2 and α1, respectively]. The dashed line shows the theoretical fit for the one site model [VCG/V0 = Ki/([CG] + Ki), with a Ki of 17.3 nM]. Each point represents the average value from four independent experiments ± SEM.