Fig. 6. Hedgehog signaling controls blastema cell proliferation. (A,B) Cumulative BrdU labeling of ependymal cells (A) and ventral blastema cells (B). Each column represents the mean percentage of BrdU-positive cells of 2-4 regenerates at indicated time intervals of BrdU labeling. Between 76 and 255 ependymal and blastema cells were counted in total per regenerate. Error bars are standard deviations. The t-test values are 0.005 at 48 hours and 0.212 at 72 hours in A, and 0.003 at 48 hours and 0.002 at 72 hours in B.