Regulatory volume decrease in SS and AA reticulocytes after incubation in isotonic media at pH 7.0. Cells with initial MCHC = 300 g/L (30 g/dL) were incubated in Cl media at pH 7.0. Results are means (± SD) of 3 experiments. (A) SS (♦) and AA (○) reticulocytes. ▵ represents SS reticulocytes in Cl-free (NO₃) media. (B) In the experiments depicted in panel A, density distributions of SS reticulocytes with high or low TO fluorescence by flow cytometry were analyzed separately. Error bars represent standard deviation.