Fig. 9.

Effect of the PKA inhibitor H89 on the adenosine (ADO)-induced inhibition of [¹⁴C]oxalate uptake by Caco2-BBE (C2) cells. C2 cells were preincubated with vehicle (Control) or 100 µM ADO for 2 min in the culture medium, and then [¹⁴C]oxalate uptake was measured as described in materials and methods. [¹⁴C]oxalate uptake was also measured in the presence of H89 (40 µM) for 30 min followed by 100 µM ADO with continued presence of H89 (ADO + H89) for 2 min or 40 µM H89 (H89) alone for 32 min. Values are means ± SE of 4 independent experiments each of which was done in triplicate and was normalized to the respective Control value. H89 had no significant effect on the inhibition induced by ADO (*P < 0.001 for ADO and ADO + H89 compared with Control, by ANOVA).