fig1

Figure 1. Liver from a mouse fed diethyl 1, 4-dihydro, 1, 4, 6-trimethyl 3, 5-pyridine decarboxylate for 1 year (×57). Note the hyperplastic nodule is devoid of brown protoporphyrin pigment, whereas the surrounding normal liver parenchyma is filled with protoporphyrin deposits