Fig. 8. Changes in AO fluorescence following (A) exposure of cells to BAPTA-AM (25 µmol l^–1) in the presence and absence of extracellular Ca²⁺ and (B) exposure of cells (pre-incubated with 25 µmol l^–1 BAPTA-AM for 1 h) to hypertonicity followed by restoration of isotonic conditions, in the continuous absence of extracellular Ca²⁺. Data are means ± s.e.m. of 61–126 cells from four to five independent preparations. Data were normalized as in Fig. 3. For comparison, the control (Fig. 2A) is shown as a dotted line in B.