Figure 4From: Impaired plasticity of cortical dendritic spines in P301S tau transgenic mice Failure to detect tau in cortical dendritic spines by means of immunohistochemistry. Immunohistochemical labeling of hyperphosphorylated tau (antibodies AT8, AT100, and AT180) in cortical layer V pyramidal neurons (a-f) and hippocampal CA3 neurons (g-j). a-a” YFP-expressing neuron, filled with somatodendritic AT8-positive tau. The marked section of the apical dendrite (dashed rectangle in a”) is shown in higher magnification in b-b”, demonstrating that the protruding YFP-positive dendritic spines (exemplarily marked by arrowheads) are bare of hyperphosphorylated tau. c Example of a YFP-negative layer V neuron (c’-c”’, magnifications of the regions marked by dashed rectangles), containing AT8-positive tau in its soma, axon (arrows in c’), basal dendrites (arrowheads in c’), apical dendritic shaft (c”), and higher-order distal dendritic braches (arrowheads in c”’). An adjacent AT8-positive layer II/III neuron shows a similar punctate pattern of hyperphosphorylated tau in its dendritic filaments (arrows in c”’), not to be mistaken for emanating spines. AT8-labeling is also found irregularly in the neuropil, for example in neuritic dystrophies (asterisks in c”’). Different from the cortex, in hippocampal CA3 neurons, AT8-positive hyperphosphorylated tau was frequently found in spiny protrusions (inset in g, arrows). Images show maximum intensity projections. In c-j, images were inverted for contrast enhancement. Scale bars: 2 μm (b), 5 μm (c” & insets d, f &g), 10 μm (a, c’, c”’, e, h-j), 20 μm (c, d, f & g).Back to article page