Early Decrease in Respiration and Uncoupling Event Independent of Cytochrome c Release in PC12 Cells Undergoing Apoptosis
Figure 6
Decrease in endogenous, DNP-uncoupled, and TMPD-dependent respiration rates in STS-treated PC12 cells pretreated with z-VADfmk and in Bis-I-treated cells. (a) Relative oxygen consumption rates of 100 μM zVADfmk-pretreated, 2 μM STS-treated PC12 cells for the indicated times. Oxygen consumption rates were measured in TD buffer (endogenous respiration, End), in TD buffer containing DNP (DNP-uncoupled respiration, DNP) and in TD buffer containing DNP, antimycin A, ascorbate and TMPD (TMPD-dependent respiration, TMPD). Data are expressed, at each time point, as percentages of the oxygen consumption of untreated cells (0 hr). Data are expressed as means ± SE with varying at each time point and being 8, 6, 6, 2, 3, 2, 3 for 1 h, 2 h, 3 h, 5 h, 9 h, and 24 h, respectively. (b) Magnification of the panel (a) area surrounded by a yellow frame. Note that the ordinate scale starts at 50%. (c) Relative oxygen consumption rates of Bis-I-treated PC12 cells for the indicated times. Data are expressed as means ± SE with varying at each time point and being 5, 6, and 5 for 1 h, 2 h, and 3 h respectively.
