MMP9 and Stroke: Moreover, phosphorylated-p38 MAPK (p-p38) levels were also significantly increased from days 2 to 14 after stroke (Fig. 5B), and the ratio of p-p38 to total-p38 (p-p38/T-p38) was significantly correlated with increased MMP-9 expression (R2 = 0.6176, P = 0.002; Fig. 5C) but showed no significant correlation with MMP-2 activity (R2 = 0.3252, P = 0.053; Fig. 5D).