Effect of 100 μmol/l serosal bumetanide on transepithelial fluxes of sulfate () and chloride () across the distal ileum from wild-type (WT) and DRA-knockout (KO) mice. Unidirectional sulfate fluxes (A and B) and chloride fluxes (C and D) were measured simultaneously across isolated, short-circuited segments of the distal ileum in standard buffer. E and F compare the responses of short-circuit current (Isc) and transepithelial conductance (GT). Each data point represents mean ± SE of n = 6 and 5 tissues taken from WT and DRA-KO mice, respectively. *Statistically significant difference (P ≤ 0.05), as determined by one-way repeated-measures ANOVA, followed by Holm-Sidak pairwise comparisons with the preceding control period (0–30 min). M, mucosal; S, serosal.