Fig. 9. (A) Effect of sequential addition of bafilomycin A1 (0.3 µmol l^–1) and BAPTA-AM (25 µmol l^–1) on the hypertonicity-induced changes in AO fluorescence. Data are means ± s.e.m. of 56–68 cells from three independent preparations. Data were normalized as in Fig. 3. (B) Changes in AO fluorescence following exposure of cells to A23187 (2 µmol l^–1) in Ca²⁺-free medium followed by BAPTA-AM (25 µmol l^–1), in the continuous presence of A23187 and absence of extracellular Ca²⁺. Data are means ± s.e.m. of 90 cells from five independent preparations. Data were normalized as in Fig. 3.