Figure 4.

Effects of exposure to 10 μM rifampin from either the apical or basolateral membranes on transepithelial [³H]digoxin (0.5 μCi ml⁻¹ total digoxin 1 μM) fluxes. Apical-to-basal (J_a−b) and basal-to-apical (J_b−a) and net fluxes (J_net=J_b−a−J_a−b) (determined as in Figure 2) following 72 h exposure to 10 μM rifampin from either the apical or basolateral surfaces alone, or both surfaces concurrently. ^*Significantly different from control values; P<0.05. Data are expressed as±s.e.mean, n=6 replicates from an individual experiment.