FIGURE 1.

(A) Propagation velocity (in mm/min) of cortical spreading depression (CSD) measured in rats from three age groups: 4–6-month, 7–12-month, and 13–18-month-old animals. Data are the means ± standard deviations from eight animals per age group. The inverse correlation between CSD velocity and age (left panel) disappeared when animals were fed a diet that was deficient in the antioxidant vitamins C and E (right panel). ^∗p < 0.05 compared to the 4–6-month-old group. ^∗∗p < 0.005 compared to the two younger age-groups (ANOVA plus Holm-Sidak test). The skull diagram illustrates the area of KCl application to elicit CSD (in the frontal cortex), the two recording points (1 and 2, on the parietal cortex), and the point of placement of the common reference electrode (R, on the nasal bones). Data in this non-published panel (A) are from our previous publication (Guedes et al., 1996). (B) Mean ± standard deviation of the CSD Propagation velocity (in mm/min) in well-nourished (left panel) and malnourished (right panel) rats. In both nutritional groups, three age subgroups were studied: 40, 120, and 700 days of life. ^∗p < 0.05 compared with the corresponding 40-day-old group. ^∗∗p < 0.05 compared with the 40-day- and 120-day-old groups. ⁺p < 0.05 compared with the corresponding sedentary groups. (C) Recordings of DC slow potential change (P) and electrocorticogram (E) of CSD illustrating failure of CSD propagation in a 700-day-old rat. Note that after being elicited by KCl, CSD reached the recording point 1, but failed to reach point 2. (D) Percentage of KCl-elicited CSD episodes that failed to propagate to the remote recording point (2). ^∗p < 0.05 compared to the corresponding younger (4-month-old) group. Data in the non-published panels (B,D) are from our previous publication (Batista-de-Oliveira et al., 2012). Traces shown in part C corresponds to panel B of Figure 3 from the paper by Batista-de-Oliveira et al. (2012). These traces are here reproduced with permission (No. 4532461257722) from the publisher.