A. Single grey-scale and coloured merged images of immunocytochemical staining against PSD-95, synaptophysin-1 (SYP1) and NPC1 proteins in a cultured hippocampal neuron from a wt mouse. Graphs show mean ± SEM of percentage of colocalization of NPC1 with PSD95 or SYP1 (n=12 neurons from 3 different cultures). 