Fig. 5

Microglial P2X7Rs are dynamically regulated by inflammatory stimuli. a The mean current density (pA/pF) of the initial ATP application (10 mM, 3 s) measured in microglia treated with LPS (1 μg/mL, 12–24 h) was 2.5-fold greater than untreated control cells (n = 54 control cells, n = 14 LPS cells; p < 0.0005; unpaired t test). b Comparison of facilitation time course between control and LPS-treated cells measured as the fraction of current recorded at the end of each successive 3-s ATP application over the initial current (n = 25 control cells, n = 7 LPS cells). c Representative patch-clamp recording of a 3-s ATP-gated current (10 mM) recorded from an untreated (non-phagocytic) human microglia cell. d Example of a microglia cell that had phagocytosed red-fluorescent E. coli bioparticles (inset photo); patch-clamp recording from this cell showed significantly increased 10 mM ATP-mediated current compared to untreated microglia. Panels c and d share a common scale bar. e The mean current density (pA/pF) of the initial ATP application (10 mM, 3 s) measured from phagocytic microglia was threefold greater than untreated control cells (n = 54 control cells, n = 23 phagocytic cells; significant enhancement by E. coli ingestion p < 0.0001; unpaired t test). f Time course of facilitation (blue symbols) or rundown (black symbols) of phagocytic microglia currents measured as the fraction of current recorded at the end of each successive 3-s ATP (10 mM) application over the initial current (n = 10 facilitation cells, n = 11 run-down cells)