Ki-67 immunoreactivity was found in astrocytes and oligodendrocytes in LPS-injected SNpc. (A) Brain sections were prepared at the indicated times after LPS-, and PBS-injection and stained with antibodies specific for Ki-67. Lower panels are higher magnification of boxed areas in upper panels. In intact contralateral (contra) sides and sections from PBS-injected brains, some Ki67+ cells were detectable (black arrows). Dotted lines at 3 and 14 d show areas where the number of Ki67+ cells dramatically increased (whiter arrows). Asterisks (*) indicate injection sites. (B) Sections obtained at 3 d were double-labeled with combinations of Ki-67/GFAP, Ki-67/Vimentin, and Ki67/Olig2 antibodies. Nuclei were labeled with DAPI. Arrows indicate cells co-labeled with Ki67 and each cellular marker. (C) Sections obtained at 7 d were double-labeled with combinations of Olig2/Vimentin and Olig2/CC-1 antibodies. Arrowheads and arrows indicate cells where Olig2 was found in the cytosol and nuclei, respectively. Scale bars, 200 μm (upper panels in A), 50 μm (lower panels in A), and 20 μm (B, C).