Zebrafish larvae (day 5) were treated with increasing doses of: A) 25D (5-150 nM), B) 1,25D (0.1-10 nM) or vehicle (0.1% ethanol) for six hours, and expression of cyp24a1 mRNA determined by qRT-PCR. Data are expressed as ΔΔCt = ΔCt (cyp24a1) - ΔCt(elfa). C) Zebrafish larvae (day 5) were treated with increasing doses of itraconazole (ITRA, 0, 0.1, and 1.0 μM) one hour prior to six hour incubation with vehicle, 5 nM 25D or 0.1 nM 1,25D. Expression of cyp24a1 was then determined by qRT-PCR and expressed relative to vehicle ITRA set to 100%. Fold = 2ΔΔCt. Data are shown as n=3 replicates ± SD. * P < 0.05.