Fig. 6.

Effectiveness of efflux transporters at preventing accumulation of transporter substrates across a concentration series (means ± s.d.). The results for concentrations of CAM and CROAM that exceed esterase capacity, 1 and 2.5 μmol l⁻¹, respectively (see Fig. 7 for absolute accumulation rates), underestimate the actual values. (A) The ratio of fluorescence for embryos exposed to maximally effective doses of the inhibitors MK571 and PSC833 or to a solvent control. (B) The same data set from Fig. 3A, but displayed as a percent instead of a ratio, where percent effectiveness is calculated as: 100×(A_I–A_U)/A_I, where A_I and A_U indicate the rate of substrate accumulation in inhibited and uninhibited embryos, respectively.