Spontaneous iron accumulation in hepatocytes of a 7-week-old female rat

Abstract

Spontaneous iron accumulation in hepatocytes was observed in a 7-week-old female Han Wistar GALAS rat. Very fine yellowish brown pigments, which showed a positive reaction with Berlin Blue stain, were apparent in the cytoplasm close to the bile canaliculi, with a diminishing periportal-to-centrilobular gradient. There were also differences in distribution between and within lobes. Transmission electron microscopy revealed cytosolic ferritin and pericanalicular siderosomes in hepatocytes. No degeneration or necrotic changes were observed, and non-hepatocyte cells did not demonstrate any obvious accumulation of iron. There were no abnormalities in the animal other than this finding in the liver.

Keywords: hepatocyte; iron accumulation; iron overload; rats; spontaneous.

Fig. 1.

A liver preserved in formalin solution. Note the reddish brown coloration.

Fig. 2.

The liver tissue shows uneven positive staining with Berlin Blue. a. H.E staining, b. Berlin Blue staining.

Fig. 3.

Very fine yellowish brown pigments showing a positive reaction with Berlin Blue stain are apparent in hepatocytes. The pigments in the cytoplasm are close to bile canaliculi, with a diminishing periportal-to-centrilobular gradient. a, c. H.E stain. b, d. Berlin Blue stain.

Fig. 4.

a. Irregular bodies filled with electron-opaque aggregates are apparent in hepatocytes. b. Very fine particles (ferritin) are distributed diffusely, without any enveloping membrane in the cytosol, as well as in single membrane-limited bodies.