Figure 3.

In vitro culture of axolotl skin explants on a polystyrene plate. Skin explants with 2 mm punch holes were cultured on 300 μg/cm², (a) to (d), and 20 μg/cm², (e) to (h) collagen-coated petri dishes. Images of the wound closure were obtained within 24 h (a) to (d) and 48 h (e) to (h). After culturing for 48 h, the wounded areas remained unable to recover completely on 20 μg/cm² collagen-coated polystyrene plate (h, dashed line). Cultured wound epithelium showed significant difference of average migration rate after 6 h incubation by unpaired t-test (i). Sample sizes for each condition were as follows: 20 μg/cm² for 6 h culture: N = 5; 300 μg/cm² for 6 h culture: N = 5. ^** P = 0.0018. Scale bars: 1000 μm.