NS1652 effect on Cl−/SO42− exchange in A/A erythrocytes.
Initial Cl− fluxes (calculated between 5 and 15 seconds after injection of the cells) versus the concentration of NS1652 (0, 1, 3.3, 10, or 20 μM). At time zero, 100 μL packed cells were transferred to vigorously stirred 3 mL isotonic SO42− exchange solutions containing various concentrations of NS1652. The increase in the extracellular Cl− concentration (insert) was followed by on-line recording of the potential from a calomel-Ag/AgCl electrode pair. The electrodes were calibrated by Cl− standards immediately before and after the exchange experiments. NS1652 had no effect on electrode sensitivity. The extrapolation of the curves to zero intercept at a higher extracellular chloride concentration than 0.5 mmol/L due to the trapped volume of high-chloride medium between the packed cells.
