Storage of excess iron in the heart and pancreas of mice after 3 months on a diet supplemented with 2.5% wt/wt carbonyl iron (Prussian blue staining, n = 5). The animals were 5 months old at the end of the experiment. Heart section from representative β2mRag1^-/- (A) and HfeRag1^-/- mice (B). Pancreas section from representative β2mRag1^-/- (C) andHfeRag1^-/- mice (D). Original magnification, × 600.