Figure 3

Elemental profiles of Fe and P across the somata of two neurons one with PN (upper cell) and one without PN (lower cell) extracted from PIXE element imaging data (tissue loaded with 1.68 mM FeCl3).
The PN (previously identified within the Ni-map, not shown) localized on the outer surface of the soma shows a local increase in iron concentration several fold above the surrounding extracellular matrix and neuropil. Scale bar: 10 μm.