Cl−/HCO3- exchange activity in fMLP-stimulated human neutrophils

► The intracellular pH changes induced by fMLP were different in neutrophils equilibrated in solutions buffered with HEPES or HCO3-. ► The fMLP inhibits the anion exchanger activation in neutrophils and this effect is independent of other pHi regulatory mechanism. ► The fMLP inhibitory effect seems to be modest, compared with others AE inhibitors, but it could work as a fine adjust when Na+/H+ activityis low. ► The HCO3-/Cl− exchange and Na+/H+ exchange are inversely regulated during neutrophil activation by chemotactic agents to allow a pHi increase.