| Abstract: | The distribution of glycogen in livers of DAB-fed rats has been examined by the PAS reaction. At early stages of DAB feeding, a loss of glycogen was observed in cells of centrolobular areas undergoing a degenerative process. Intense glycogen staining was shown, on the other hand, by the hyperplastic nodules which develop from cells of periportal areas. At later stages, the formation of hyperbasophilic foci was found to be accompanied by a loss of glycogen, and the hepatomas, which apparently arise from such foci, were PAS-negative. It thus seems that a radical change in glycogen metabolism is associated with the neoplastic transformation. Alterations inglycogen metabolism being considered irrelevant to neoplasia per se, these results suggest that hyperbasophilic foci are the sites not only of modifications in the regulation of the cell cycle that initiate neoplastic growth but also of parallel changes responsible for secondary features of tumors. |
