Abstract
1. Observation was made to find whether the pyridoxine palmitates had the atoxoprimidine (ATXP) activity in mice.
2. It was found that the sensitivity of mice to 2-methyl-4-amino-5-hydroxymethyl pyrimidine (OMP) increased by feeding a synthetic vitamin B6-deficient diet for 7 days was depressed by feeding the deficient diet supplemented with the pyridoxine palmitates equimolecular to PIN-HCl.
3. In the experiments of oral and subcutaneous administrations in a single dose at various intervals before and after the OMP injection, it was found that the PIN palmitates exhibited the ATXP effects when administered one to 24 hours before the OMP injection and that the maximum effect was seen 6 hours before the OMP injection, while the activity of pyridoxine hydrochloride was maximum when administered simultaneously with OMP and exhibited no activity when administered 24 hours before OMP injection.
4. In the above experiments, the ATXP activity of pyridoxine dipalmitate was stronger than pyridoxine tripalmitate.
5. When the pyridoxine palmitates was injected intraperitoneally in a single dose, only a slight activity of ATXP was observed.
6. It was suggested that the apparent ATXP activity of the PIN palmitates was possibly due to the pyridoxine produced by hydrolysis in vivo.
