Chronic neuronal activity inhibition by TTX reduces extracellular amyloid in APP^Swe/PS1^L166P mice.

<p>Upper panels: quantitative analysis of amyloid load in the extracellular compartment in hippocampus (<b>A</b>; <b>B</b>) and entorhinal cortex (<b>C</b>; <b>D</b>) in terms of plaque number (<b>A</b>; <b>C</b>) and plaque size (<b>B</b>; <b>D</b>) in APP^Swe/PS1^L166P mice treated with TTX or vehicle alone. The analysis showed an increase of plaque number (<b>A</b>; <b>C</b>) but not of plaque size (<b>B</b>; <b>D</b>) after TTX administration in hippocampus (<b>A</b>; <b>B</b>) and entorhinal cortex (<b>C</b>; <b>D</b>) (n = 5 in each group, three sections per mouse, three frames per section, <i>* P</i><0.05, *** <i>P</i><0.001, Student’s <i>t</i>-test). Error bars represent SEM. Lower panels: representative images of coronal hippocampal (<b>E</b>; <b>F</b>) and entorhinal cortical (<b>G</b>; <b>H</b>) sections of APP^Swe/PS1^L166P mice treated with vehicle (<b>E</b>; <b>G</b>) or TTX (<b>F</b>; <b>H</b>), immunostained with 6E10 antibody. Note the decrease in the number of plaques in hippocampus and in entorhinal cortex after TTX. Calibration bars, 300 µm. (HIP, hippocampus; EC, entorhinal cortex).