Some observations on the structure of Suncus liver with special reference to the vitamin A-storing cell.

The structure of the liver of the thick-tailed shrew (Suncus murinus) was studied with special reference to the vitamin A-storing cell. The macroscopic arrangement of hepatic lobes was the same as those of rodents. Connective tissues of Glisson's sheath were not prominent. There were gradual differences in the size and the cytoplasmic contents of hepatocytes among perihepatic, intermediate, and periportal regions. These correspond to the acinar zones 3, 2, and 1 of Rappaport, respectively. The ultrastructural features of the hepatocyte were numerous microvilli, a large mass of glycogen particles (alpha-particles), and well-developed Golgi complexes and lysosomes in the peribiliary region. Cellular elements of the sinusoid were the same as those of rodents. Vitamin A-storing cells were demonstrated by autoradiography of tritiated retinyl acetate administered orally. They were distributed in the perihepatic and intermediate regions. The number of vitamin A-storing cells was much smaller than that in the mouse liver and did not increase after excess vitamin A was given to the animal. Cytological features of the vitamin A-storing cells in Suncus liver were similar to those for other mammalian livers. The scarceness of vitamin A-storing cells and the low amount of vitamin A esters suggest that Suncus does not store much vitamin A in the liver.