1979 年 12 巻 4 号 p. 361-367
Wistar SLC male rats were injected with 25mg/Kg of 7, 12-Dimethyl-benz(α)anthracene intravenously twice at 51 and 66 days of age, and also fed on a commercial diet containing 4-Dimethylaminostilbene, 0.004%, from the age of 57 days to the respective days of their decapitations. Fresh cryostat serial sections of Zymbal glands were examined by histochemical methods for SDH, LDH and G6PDH 6, 11 and 17 weeks after the first injection. Either atypical hyperplasia of the acinar cells or microtumor was detected in the Zymbal glands of almost all treated rats 11 weeks after the first injection. An ear duct tumor was induced in all treated animals 17 weeks after treatment. SDH and G6PDH activities decreased progressively in the tumorigenesis, but moderate LDH activity remained in the tumor tissues. Biochemical determinations for LDH and MDH in the Zymbal glands harvested serially 4-20 weeks after the first injection of DMBA indicated that the quotient of LDH/MDH began to elevate 8-11 weeks after injection and elevated in the tumorigenesis owing to a progressively lower MDH.
