Changes in mTOR and p70S6K activation after chronic LPS-induced inflammatory stress. Representative immunoblots showed the immunoreactivity of mTOR, PS2448-mTOR, p70S6K, PT389-p70S6K in cortex (A) and in hippocampus (B) from LPS-treated mice (0.5mg/kg of LPS every 3 days for 3 months) or control (0.9% NaCl every 3 days for 3 months). Treatment started at 3 months and mice were sacrificed at 6 months of age. Semi-quantitative analysis of immunoblot was performed using Gene Tools software (Syngene, Ozyme France). The immunoreactivity of protein was normalized to β-tubulin immunoreactivity. The results are expressed as arbitrary units ((% of 0.9% NaCl-injected mice group set at 100%). Results are mean±SEM for 6 mice in each group. **p < 0.01 compared to control mice by a Mann-Whitney test.