Fig. 6. The time course of ONOO^– secretion into the extracellular medium upon PMA stimulation. (a) The live cell imaging of the ONOO-CBP labeled RAW264.7 cells in (i) the absence or presence of 1 μg mL^–1 PMA after incubation for (ii) 10, (iii) 20, (iv) 40, (v) 60, or (vi) 80 minutes. Scale bar: 20 μm. (b) The time course of the mean fluorescence intensity (processed using Image J) on the cell surface of the RAW264.7 cells treated with 1 μg mL^–1 PMA (N = 30 for each indicated time). The cells were stained with streptavidin–Cy5. Scale bar: 20 μm.