Figure 3. CBF responses to changing pH_i during removal of external CO₂.

A, simultaneous CBF and pH_i recording from a single, submerged, BCECF-loaded human tracheobronchial epithelial cell, mounted into a closed chamber and perfused with CO₂/HCO₃⁻-buffered solution (solution 7, Table 1) in exchange with CO₂/HCO₃⁻-free, Hepes-buffered solution (solution 6, Table 1). B, correlation between CBF and pH_i plotted from the experiment shown in panel A. C, correlation between CBF and pH_i plotted from 13 cells during and after removal of external CO₂ identical to the experiment shown in panel A.