(A) wnt activity in the kidney marrow was enhanced in FACS profiles on day 3 post irradiation (dpi) in TOP:dGFP fish; representative FACS analyses are shown on the left, and summarized (mean ± SD) on the right. dmPGE2 further increased and indo inhibited wnt activity; *sig vs unirradiated con, **sig vs irradiated con, ANOVA, p<0.001, n=5 fish/treatment. (B) wnt8 (bottom left panel) enhanced the precursor population (red), while indo suppressed that effect significantly; *sig vs con, **sig vs wnt8, t-test, p<0.02, n=10–15. (C) dkk reduced progenitor recovery, which was rescued by dmPGE2; *sig vs con, ***sig vs dkk, ANOVA, p<0.05, n=6.