[Ultracytochemical study of the nucleoside phosphatase activity of nuclei of epithelial cells of the gastric mucosa and of stomach cancer cells in humans].

Ultracytochemical study was made of inosine diphosphatase (IDPase) and adenosine triphosphatase (ATPase) in the nuclei of normal epithelial and cancer cells of human gastric tumors. A new incubation medium for ultracytochemical demonstration of IDPase activity in the cell nuclei was developed. The activity of IDPase and ATPase in the nucleoplasm and in the nucleoli of the tumor cells was shown to be lower than in respective normal cells. IDPase activity in the nuclear envelope in the tumor cells was absent in contrast to the normal cells.