Fig. 8. Effect on E_m and R_in of reducing the extracellular osmolality in the presence of Cl^– channel blockers and in Cl^–-free solution. The preparations were exposed to the Cl^– channel blocker DIDS (0.5 mmol l^–1) or NPPB (50 µmol l^–1), or to isotonic Cl^–-free solution (Cl^– replaced by gluconate), and after 5 min E_m and R_in were measured. Subsequent reduction of the extracellular osmolality by omitting 40 mmol l^–1 NaCl or sodium gluconate from the bath solution caused changes in E_m (A) and R_in (B) that were determined after 5 min. Significant differences from the control data (taken from Fig. 4, broken line) are indicated by asterisks (^**P<0.01).