Fig. 1

Altered APE1/Ref-1 expression in the kainic acid (KA)-injured hippocampus. a APE1/Ref-1 immunoreactivity in the hippocampus at 1, 3, and 7 d after KA injection. Higher magnification of areas in CA3 region of the hippocampus showed sequential changes of APE1/Ref-1 expression (lower panel; scale bar = 20 μm). Note that APE1/Ref-1-ir appeared in small nuclei and short processes (glial morphology, white arrowheads), or faint nuclei and dense cytoplasm (white arrows) in KA treated hippocampus, while it mostly appeared in the round nuclei in control brain (blue arrowheads). b Representative photomicrographs from the double immunofluorescence staining for APE1/Ref-1 (red) and GFAP (green) in the CA3 region of KA-treated hippocampi (3 d after KA injection). APE1/Ref-1 was found in the processes (white arrowheads) and perinuclear cytoplasm (white arrows) of GFAP-positive astrocytes. Nuclei were counterstained with DAPI (blue). c Quantitative analysis of double immunofluorescence staining for the identification of APE1/Ref-1-positive cells in the KA-injured hippocampus. The portion of APE1/Ref-1-positive cells out of total glial fibrillary acidic protein (GFAP)-positive cells was compared at 1, 3, and 7 d in the KA-injured hippocampus. ***P ˂ 0.001 vs. saline-injected control. d Representative photomicrographs showing that GFAP-positive cells expressed iNOS in the KA-treated groups. Nuclei were counterstained with DAPI (blue). e Representative photomicrographs showing that APE1/Ref-1 was expressed in reactive astrocytes in the LPS-treated hippocampi (1 d after LPS injection). APE1/Ref-1 was found in the processes and cytoplasm of GFAP-positive astrocytes (white arrowheads). Nuclei were counterstained with DAPI (blue). Scale bar = 200 μm (or 20 μm, in set). f Quantitative analysis of double immunofluorescence staining for the identification of APE1/Ref-1-positive cells in the LPS-injured hippocampus. ***P ˂ 0.05 vs. saline-injected control