Relative mRNA Expression of astrocyte activation markers in Hippocampus of adult and aged mice following CCI injury analyzed by real-time RT-PCR. GFAP (A) and S100B (B) mRNA expression was studied after 1, 2, 3, 7, 14 and 28 days after injury. The real time reactions were performed in duplicates for both the target gene and GAPDH used as a housekeeping control. The relative expression was calculated using delta delta CT method. Data are presented as mean ± SEM (n=5/group). Asterisk denotes statistical significance after ANOVA and post-hoc testing where *p < 0.05, **p < 0.01, ***p < 0.001 vs. adult