Vitamin B6Levels in Rat Tissues

Abstract

Wistar strain albino rats were pair-fed a vit. B6-free diet with and without the antivit. deoxypyridoxine HC1 (100 [mu]g./day). Control rats received 50 [mu]g./day pyridoxine HCl in the food. During simple deprivation of dietary Bg, the vit. concn. in the liver decreased at a relatively steady rate for the first 4 wks. and then steadied at a minimal level. Where deoxypyridoxine was administered the liver vit. Bg concns. were similar but acrodynia symptoms appeared more quickly after minimal level was reached. The ratio of carcass content: liver content of vit. Bg increased in control rats but remained constant in deprived rats, suggesting that storage of the vit. occurs in extrahepatic tissue and that such stores can be mobilized to the liver during restriction of dietary B6. The concn. and mobility of liver stores of vit. Bg suggests that the liver is more useful than the heart or kidney for assessing vit. Bg nutrition in the rat. Liver pyridoxine concns. showed a fairly constant level on an intake of 15-25 [mu]g. B6/rat/day, however, [mu]g. body wt. gains continued to increase even beyond an intake of 25 ug. pyridoxin/rat/day, which suggests the liver may become saturated below the pyridoxine level necessary for max. growth.