Effect of hepcidin on iron absorption in iron-deficient mice. Mice were fed an iron-replete (C) or iron-deficient (ID) diet for 3 weeks from weaning and injected with 0.15 M NaCl (sal) or hepcidin (50 μg single injection) on each of 2 consecutive days, 24 hours before measuring iron absorption with tied-off duodenal segments. Data (means ± SEM) shown are mucosal retention (▪), transfer of radioiron to the carcass (▦), and total mucosal uptake of radioiron (□). Significance of effects was analyzed by ANOVA and is shown in Table 3. *P < .05, **P < .01 compared with mice fed the same diet and injected with saline.