Abstract
The effect of vitamin B6 on experimental carcinogenesis in rats by dimethylaminoazobenzene (DAB) was studied and the following results were obtained.
1. Carcinogenesis by DAB was highest and the pathological changes were severest in the group receiving an excessive dose of vitamin B6. The rate of carcinogenesis was higher in the group receiving excess pyridoxamine than with excess pyridoxine.
2. The rate of carcinogenesis is higher in vitamin B6-deficient group, compared to the control, but its mechanism is considered to differ from that in excess vitamin B6 group.
3. By loading with DAB, the lymphocytes in the peripheral blood showed a slight rise after 1-2 months, followed by a sharp fall after 3-4 months. Lymphocytes containing a small number of mitochondria gradually rose with time. This is especially pronounced in the animal given excess vitamin B6 showing a trend of carcinogenesis of the individuals.
4. The catalase activity of both liver and blood decreased by the administration of DAB. It was most pronounced when excess vitamin B6 was given.
It is clear that excess vitamin B6 enhances DAB liver carcinogenesis, but it also enhances the growth of the tumor. Contrary to the previous reports, carcinogenesis was rather high in vitamin B6 deficiency and it was lowest when an appropriate amount of vitamin B6 was given. It is believed to be a fact of great importance.
