Fig. 8.

Concentration dependence of mucosal DIDS inhibition of oxalate and chloride transport across Con (○, n = 6) and A6KD (•, n = 6) Caco-2 monolayers 6–8 days postseeding in standard bicarbonate buffer. A: effect of DIDS on J_MS^Ox. The percent inhibition was calculated relative to the mean J_MS^Ox measured in Per I of all controls used in this series (25.6 ± 1.3 pmol·cm⁻²·h⁻¹, n = 42). The G_T for Con in Per I (2.89 ± 0.08 mS·cm⁻²) was not significantly different from G_T in A6KD monolayers (2.78 ± 0.09 mS·cm⁻²). In B, the effect of DIDS on J_SM^Ox is shown. Again, the percent inhibition was calculated relative to the mean J_SM^Ox measured in Per I of all controls used in this series (26.8 ± 1.9 pmol·cm⁻²·h⁻¹, n = 42). Conductances in Per I were similar to those presented in A. C: concentration dependence of mucosal DIDS inhibition of J_MS^Cl in Con (n = 5) and A6KD (n = 5) monolayers. The percent inhibition was calculated relative to the mean J_MS^Cl measured in Per I of all controls used in this series (4.26 ± 0.13 pmol·cm⁻²·h⁻¹, n = 30). The G_T for Con in Per I (2.65 ± 0.43 mS·cm⁻²) was not significantly different from that of A6KD monolayers (2.46 ± 0.11 mS·cm⁻²). In each panel the dashed line through the shaded squares represents the dose-response curve for SLC26A6 exchanger alone (i.e., the difference between Con and A6KD monolayers). Error bars represent ±1 SE.