Cu/Zn-SOD and Mn-SOD mRNA expression in rat diaphragms. Real-time RT-PCR for Cu/Zn-SOD, Mn-SOD, and endogenous control GAPDH mRNA expression was performed using a SYBR green assay. All the data were analyzed using Rotor Gene 5 software (Corbett Research, Sydney, New South Wales, Australia). The values for Cu/Zn-SOD and Mn-SOD were normalized to the levels of the GAPDH gene. Diaphragm samples were assayed for Cu/Zn-SOD and Mn-SOD mRNA levels by (A) western blot analysis and (B) real-time quantitative PCR analysis (n=6 in each group). The bars represent the means ± SEs, and *indicates significance at the P<0.05 level compared with the control group.