TABLE 5
Model parameters generated by fitting an inhibitory concentration-response model by nonlinear regression
Parameters were generated using the equation: Net efflux = Tmax · (1 – [Conc.γ/(IC50γ + Conc.γ)], where Tmax = net efflux without inhibitor (× 10-6 cm/s), Conc. = inhibitor concentration (μM), IC50 = concentration of inhibitor resulting in 50% of maximum inhibition (μM), and γ = sigmoidicity factor that determines the slope of the relationship. The standard errors (S.E.) are estimates of the precision of the parameter estimates.