Fig. 3

A Representative microscopy images of triple staining with Ki67, paired box 7 (Pax7), and 4ʹ,6-diamidino-2-phenylindole dihydrochloride (DAPI) on day 1 after basic fibroblast growth factor (bFGF) (2000 ng: high dose) injection in the paralyzed side, or saline injection in the paralyzed side or non-paralyzed side (400 × magnification). The number of Ki67⁺ proliferating cells and Pax7⁺ SCs in the paralyzed side of the high-dose group was higher than that in the non-paralyzed and paralyzed side of the saline group. Moreover, most Ki67⁺ proliferating cells were co-expressed with Pax7 in the high-dose group. White arrows indicate Ki67⁺ or Pax7⁺ cells. Yellow arrows indicate Ki67⁺ /Pax7⁺ cells. B Temporal changes in the ratio of Ki67⁺ and Pax7⁺ cells to muscle fibers after bFGF injection in the paralyzed side or saline injection in the paralyzed or non-paralyzed side. Error bars represent the standard deviation. **P < .01, Tukey’s multiple comparisons tests. C Temporal changes in the ratio of Pax7⁺/Ki67⁺ cells in all Ki67⁺ proliferating cells in the high-dose group. The ratios were almost 1 on days 1 and 7, indicating that most Ki67⁺ proliferating cells were Pax7⁺ SCs. NPS, non-paralyzed side of the saline group; PS, paralyzed side of the saline group; High-dose group, paralyzed side of the high-dose basic fibroblast growth factor group