Fig. 4. Typical experiments showing the effect of ouabain on basolateral membrane potential (V_bl) in the presence of glibenclamide (Glib.) and Ba²⁺. The hyperpolarization (A) or depolarization (B) of glibenclamide and Ba²⁺ is followed by a depolarization of V_bl with the addition of 1 mmol l^-1 ouabain. The experiments were carried out in low bath [K⁺] (5 mmol l^-1).