Fig. 5.

Responses to OPZ of bone marrow phagocytes from WT and HVCN1 deficient (KO) mice. (A) Phagocytes from KO mice have no proton current. Currents are for pulses to +100 mV before (Left) and after (Right) 150 nM PMA. (B) Electron current elicited by PMA in the same cell at +20 mV, showing inhibition by 20 μM DPI, an NADPH oxidase inhibitor. (C) PMA response of WT proton currents during pulses to +80 mV applied at 1-min intervals before and after PMA. (D) Electron current elicited by PMA at −40 mV in the same cell. (E) Average time course of pH_i in mouse bone marrow phagocytes exposed to OPZ. Each cell was retrospectively synchronized so the first phagocytotic event occurred at 1.5 min. Measurements in cells from 3 different mice are combined for each condition. Mean ± SEM is plotted for 32 WT cells (■), 21 WT cells with 100 μM Zn²⁺ (▴), 23 KO cells (▵), and 18 KO cells with 100 μM Zn²⁺ (◇). At 6 min, KO, KO+Zn²⁺, and WT+Zn²⁺ all differ significantly from control (P < 0.01), but not from each other, with the exception that KO+Zn²⁺ differs from KO (P < 0.05). (F) Maximum rate of pH_i decrease during the initial phagocytotic event in mouse bone marrow phagocytes. Mean ± SEM is plotted for 34 WT cells, 22 WT cells with 100 μM Zn²⁺, 24 KO cells, and 18 KO cells with 100 μM Zn²⁺. All data differ from WT (P < 0.001), but not from each other.