Expression and distribution of CXCR4 protein in spinal cord after TCI in rats. (A) Western blot analysis shows time course of CXCR4 expression in sham and TCI rats. Five spinal cord segments were included in each group. Representative bands are shown on the top; data summary is shown on the bottom. **P < 0.01 indicate significant differences compared with group of sham control. (B) Immunofluorescence shows expression of CXCR4 protein (green) in rat spinal cord at different time points. Tissues were collected at day 3, 5, 10 and 14 after TCI. Original magnification: 200× for all the confocal images showing the dorsal horn ipsilateral to TCI (bar = 100 μm).