Fig. 5.

Morphology of the liver in WT and KO mice. Hematoxylin and eosin staining shows normal liver morphology in adult WT (A) and KO (B) mice that were maintained on a normal diet. However, after 4 mo on a high-fat diet, sections from WT mice (C) clearly showed the presence of lipid in hepatocytes (black arrows), while lipid accumulation appeared to be significantly reduced in the liver from KO mice (D). In panels A–D the white space surrounding the hematoxylin-stained nuclei indicates where lipid was localized prior to dehydration of the sections. E: toluidine blue staining of plastic sections revealed large, well-formed lipid droplets (black arrows) in hepatocytes from WT mice maintained on a high-fat diet. F: in contrast, very few, and much smaller, lipid droplets (black arrow) were visible in liver sections from KO mice maintained on a high-fat diet. Foci of hematopoiesis (white arrow) were visible in some liver sections from KO mice maintained on a high-fat diet, although they were never detected in liver sections from WT mice.