Quantification of presynaptic protein levels upon activity withdrawal. A–E, Examples of immunostainings for various presynaptic proteins in control (C) and silenced (S) cultures. The left images are overlay images with MAP2 staining (in magenta); middle images, fluorescence staining for the analyzed protein (green in overlays); and right images, overlay images with synaptophysin (in magenta). Scale bar (in E), 5 μm; applies to all panels. F, G, Quantification of numbers of puncta along a 20 μm segment of dendrites (F), and average intensity of staining (G). Values are averages from two independent experiments and are normalized to control. Bars represent the mean values; whiskers, SEM. The statistical significance was assessed using a t test; *p < 0.05; ^#p < 0.0001.