Figure 8. Surgery/Anesthesia altered the activity level of SOD and ROS in the hippocampus and prefrontal cortex of aged mice at 0, 6, 9, and 24 hours postoperatively. SOD and ROS levels were measured in fresh homogenates from hippocampal and prefrontal cortex tissues of mice at 0, 6, 9, and 24 hours after Surgery/Anesthesia or control treatment. The level of ROS in the hippocampus (A) and prefrontal cortex (B) of mice in the Surgery/Anesthesia group increased significantly compared to that in the control mice at all the postoperative timepoints. Conversely, the SOD level in the hippocampus (C) of mice in the Surgery/Anesthesia group decreased significantly compared to that in control mice at 0, 6, 9, and 24 hours postoperatively. (D) The level of SOD in the prefrontal cortex tissues of mice in the Surgery/Anesthesia group decreased significantly as compared to that in control mice at 0, 9, and 24 hours but not 6 hours postoperatively. The data are plotted as the mean ± standard error of the mean for each group (n = 6). *p < 0.05 and **p < 0.01, compared to control.