Fig. 7. ( A ) Propidium iodide staining and fluorescence-activated cell-sorter analysis after treatment with 40 mm lidocaine or without 10 μm SB203580. Fluorescence intensity (FL2-H) of detected particles is an indicator for the DNA content of the cell. The cells with subdiploid DNA content (lower FL2-H than the G0/G1-phase peak) represent the fraction undergoing apoptotic DNA degradation. Data are presented as mean ± SEM of three independent experiments. ( B ) Quantitation from of pheochromocytoma cells either untreated or stimulated with 40 mm lidocaine with or without 10 μm SB203580 using propidium iodide staining. *** P < 0.001. ctr = control; L = lidocaine; SB = SB203580.