Figure 3.

Dual pS193/pT196 tau and total tau expression in brain tissue of two month post-SE rats. (A) Representative western blot of phosphorylated tau expression in CA3 hippocampal region using the AT8 Ab showing a decrease in phosphorylated tau expression in chronic epilepsy. Shown are three different loading amounts for naïve and epileptic conditions. Phosphorylated p2N4R human tau and human tau ladder served as positive and negative controls, respectively, for the detection of phosphorylated tau. (B) Representative western blot of total tau expression in rat CA3 hippocampus using the Tau-5 Ab demonstrating a modest reduction in total tau expression in chronic epilepsy. The human tau ladder provided a size reference. (C) Group data showing changes in tau expression in chronically epileptic rats at two months post-SE in the whole hippocampal formation, CA1 hippocampus, CA3 hippocampus, and somatosensory cortex (SSC) compared to age-matched naïve rats. Values shown are individual data points; boxes denoting median, 75^th and 25^th percentiles; whiskers showing 95^th and 5^th percentiles; and mean value (diamonds). Only the CA1 and CA3 hippocampal regions of chronically epileptic rats showed significantly reduced dual pS193/pT196 tau (green box plots). Reductions in total tau expression were found in every region, including the SSC (red box plots). No changes were observed in fractional dually phosphorylated tau (pS193/pT196 tau/total tau) in any region (blue box plots).