Fig. 6.

Representative I_sc experiment in which the basolateral membrane was permeabilized with nystatin and a mucosal to serosal chloride gradient was established by replacing all basolateral Na and K salts with Na and K gluconate. The experiment demonstrates that CNP, amrinone, and forskolin stimulate chloride transport by the opening of anion channels in the apical membrane under conditions of a clamped electrochemical gradient of Cl⁻ across this membrane. The experiment is representative of 3 similar experiments.