FIGURE 4.

Illustrations of consequences of the correlation between RBC area (A) and volume (V). (A) Coefficient of variation of RBC reduced volume (CV_v) in dependence on the correlation coefficient ρ_A,V obtained for the values of coefficients of variations of RBC volume and membrane area to be 0.12 and 0.13, respectively (reprinted with permission from Svetina et al., 2019). CV_v at ρ_A,V = 0.96 is about 0.06. (B) Evidence for the role of Piezo1 based regulation of RBC volume on the mouse RBC V – A correlation. Cahalan et al. (2015) measured osmotic fragility of normal (WT) and of Piezo1 knocked out (Vav1-PicKO) mouse RBC in the absence (+Veh) and presence (+A23187) of Ca²⁺ ionophore A23187 (reprinted with permission from Svetina et al., 2019). In Figure 5 of Svetina et al. (2019) we added to Figure 3D of Cahalan et al. (2015) the column of the corresponding coefficients of variation (CV_h) obtained from steepness of osmotic fragility curves as indicated by red dashed lines.