Fig. 6

Element maps of glial cells. Light microscopy (LM) and element images (Ni, P, Fe) of the rat cortex specifically stained for oligodendrocytes, astrocytes, and microglia. The staining is enhanced with DAB-Ni (black in LM and high concentration in Ni) to identify and visualize the glial cells by elemental imaging. Glial iron concentrations were extracted from regions of high Ni concentration, which corresponds to the stained glial cells. White arrowheads in the oligodendrocyte and astrocyte images indicate somata of other neuronal/glial cells than the targeted ones (P-rich indicates glial cell, but Ni-negative excludes the target cells). Yellow arrowheads in the astrocyte images point to astrocytes where the somata, shown by the high Ni concentration, but not the nuclei (P-rich) were contained in the \(5\,\upmu \hbox {m}\) thin brain section