Cytokine-stimulated superoxide flashes in chondrocytes <i>in situ</i>.

<p><b>A</b><b>B</b>, Time-lapse views of a typical superoxide flash <i>in situ</i> in the red boxed region of 2.5 µm×5 µm. Time course plot of the superoxide flash is shown at the bottom. Note the swelling of the mitochondrion during the flash. <b>C</b>, Activity and properties of chondrocyte superoxide flashes i<i>n vitro</i> (510 events as in Figure. 2) and <i>in situ</i> (30 events). Data are reported as the mean ± SEM values. *, <i>p</i><0.05; **, <i>p</i><0.01. <b>D</b>, Time course of the superoxide flash response to cytokine stimulation. Data are reported as the mean ± SEM values. n = 21–29 imaging planes. *, <i>p</i><0.05; **, <i>p</i><0.01 versus the respective control.