Figure 1.

Suppression of caudal fin regeneration after amputation in VPA-treated zebrafish. (A) Images show the regenerated fin in each group at 2, 6, and 14 dpa. Arrowheads indicates the amputation site. Scale bar, 2 mm. (B) Bars indicate the regeneration ratio of length, segments, and bifurcating ray at 14 dpa. Data were expressed as the means ± S.E.M (n = 3). * p < 0.05 compared to the control. (C) Images show Alcian blue and alizarin red staining of cartilages and bones at 14 dpa. (D) Abnormal segments induced by 100 µM VPA treatment during regeneration. Scale bar, 1 mm. (E) Left: The regenerated intra-ray structure is schematically represented. A black dotted line, the amputation site. b, blastemia. m, mesenchyme. l, lepidotrichia. Right: Hematoxylin and eosin staining images show the transverse sections of intra-ray. The irregular-shaped lepidotrichia was shown in 100 µM VPA-treated zebrafish. Asterisks, bony skeletal structure. Arrow heads, actinotrichia. Scale bar, 500 µm.