Figure 1

Characterization of NPC1^-/- septal cholinergic neurons. A. Brain sections at the level of the medial septum (MS) from 8-week-old WT and NPC1^-/- mice were stained for ChAT and visualized with secondary antibodies conjugated to HRP. The insets show a magnification of the cholinergic cells in the upper panels. WT cholinergic neurons are smaller and less rounded than NPC1^-/- cholinergic neurons, and there is a reduction in the number of cholinergic fibers surrounding the labeled NPC1^-/- cholinergic cells. B. The number of ChAT-labeled cholinergic neurons was quantified in the septal area of WT and NPC1^-/- brain sections. Four sections from six WT and six NPC1^-/- age-matched mice were used for quantification. There are no differences in the number of septal cholinergic neurons, p = 0.829. C and D. The morphology of septal cholinergic neurons was evaluated in ChAT-stained brain sections from WT and NPC1^-/- mice. NPC1^-/- cells have an increased area and exhibit a higher ratio between the minor and major axes of cholinergic neurons, * p < 0.006. A total of 600 cells from six WT and six NPC1^-/- age-matched mice were used for quantification. E. Quantification of p75-labeled cholinergic fibers in different septal regions without cholinergic neuronal somas, as shown in the insets of Additional file 2: Figure 2A, *p < 0.0001.