Fig. 1.

Effect of forskolin (FSK) on short-circuit current (I_sc) and K⁺ fluxes in rat distal colon. A: time course of I_sc in the absence and in the presence of FSK. FSK (10 μM) was added to serosal bath (arrow). B: mucosal to serosal (m-s), serosal to mucosal (s-m), and net K⁺ fluxes (net) were measured in the absence (white bars) and in the presence (black bars) of FSK. Both I_sc and K⁺ fluxes were measured under voltage-clamp conditions. *P < 0.001, compared with respective fluxes in the absence of FSK.