Fitted parameter values of efflux active Pgp for each cell line relative to the MDCK-MDR1-NKI line and K_QB for the digoxin basolateral transporter from digoxin transport inhibition.

aThe surface density of efflux active P-gp relative to MDCK-MDR1-NKI cells, Table 2, is fixed by the average of the amplitudes of the inhibition curves for each cell line at the lowest inhibitor concentration. No error bars are given since these values were simply fitted to the digoxin concentration at the lowest inhibitor concentration by a single digit value. bThe “effective” binding parameter of the inhibitors to a basolateral transporter which block digoxin transport. Error bars were taken as single digit values to the fits.