Effect of Vitamin D on Binucleated Cells of the Liver. ∗

Abstract

It has long been known that among the cells of the mammalian liver, there are some which have more than one nucleus. Most of such multinucleated cells contain two nuclei and are thus called binucleated hepatic cells. During fetal life only small numbers of binucleated cells are found, but after birth the number gradually increases until adolescence, after which time, under normal conditions, the number of cells remains constant. Each animal species has a definite percentage of binucleated cells which is equal in the various lobes of the liver and is more or less characteristic of the species. 1 Several investigators have shown that there are more binucleated cells at the periphery of the lobules than at the center. 2 , 3 Although there is no conclusive evidence to support the idea, these cells are supposed to result either from hyperactivity and incomplete karyokinesis or from fusion accompanying degeneration. 4

Szittay 3 reported that the daily administration of 3 cc of Vigantol over a period of 8 days to young rabbits led to an increase in the number of binucleated cells in the periphery of the lobule, although no changes were found in the central zone. The number of cells with 3 and 4 nuclei was slightly increased in the same region, but there was no increase in the number of mitoses. Szittay thought that his findings indicated increased activity in the peripheral zone of the lobule rather than a toxic action of vitamin D upon the liver. These observations are of interest because clinical and experimental studies suggest that the liver plays an important role in the action of vitamin D. 5 , 6 , 7 Since Szittay's experiments seemed to constitute anatomical evidence of the action of vitamin D on the liver it was decided to repeat them.