Figure 6. Carbachol-induced K⁺ secretion on mice colon.

After pre-incubation with indometacin (2 μm), colonic strips were challenged with carbachol. The inhibitory effect of indometacin on the cAMP-induced anionic secretion unmasked K⁺ secretion that was enhanced in the IK1 KO tissue (B) compared with that of the WT animal (A). The K⁺ secretion was not inhibited by clotrimazole but partially blocked by apical Ba²⁺ in both animals. C shows ΔI_sc calculated for each condition. Values are means ±s.e.m., n = 4 (+/+) and n = 6 (−/−). *Significantly different from +/+ control; **significantly different from −/− control (t test).