Figure 6: In vitro structural plasticity of dendritic spines.

(a) Cumulative distributions of spine motility showing its increase in acute cortical slices both after ChABC treatment in vivo (red trace) and after 2 h of CSPG digestion in vitro (green trace). (b) CSPG staining (red) of a control slice (left) and after a 2 h digestion in vitro (right). Scale bar, 30 μm. (c) Examples of filopodia and filopodial protusions after 3 days of ChABC treatment. Scale bar, 2 μm. (d) Left panels: sample images taken before and after Chem-LTP (scale bar, 4 μm). Arrowheads point to spines whose volumes are reported with identical colours in the central panels. Here, volumes of spine heads have been measured before and after Chem-LTP. Changes are not significant in control, but are highly significant in the slice from the ChABC-treated mouse (paired t-test). The volume is measured by an adimensional parameter described in Methods. Right panels show the cumulative distributions of spine head volume before and after Chem-LTP in control (upper graph) and ChABC-treated (lower graph) mice.