monoclonal mouse anti-calbindin 28 K (Sigma, 1:200); monoclonal mouse anti-MBP (SMI-99, Sternberger Monoclonals Inc., 1:50); monoclonal mouse anti-Neu N (CHEMICON, 1:100); rabbit anti-S100 polyclonal (DAKO, 1:200). Nuclei were counterstained with 1 μg/ml DAPI (Sigma). MBP staining was performed after microwave epitope retrieval in 10 mmol/L citrate buffer (pH 6). Sections were incubated for 1 hour with secondary antibodies: Cy3-labeled donkey anti-rabbit IgG (Jackson Immuno Research, 1:200), FITC-labelled donkey anti-mouse IgG (Jackson Immuno Research, 1:200). Sections were photographed with an Olympus microscope (Olympus IX71) equipped with a high-resolution CCD camera.