Influence of Dietary Pyridoxine on Cadmium Toxicity in Rats

Abstract

The influence of 0, 22, and 44 ppm dietary pyridoxine (B₆) upon the toxicity of 100 ppm dietary cadmium (Cd) was studied in rats. The most significant observation was an inverse correlation between the hematocrit readings of the Cd-toxic rats and their level of dietary B₆. This interaction occurred prior to any significant differences among the cumulative Cd intakes. The Cd-toxic rats also exhibited polychromatophilia, incisor depigmentation, hypoferremia, cardiomegaly, splenomegaly, iron depletion of liver and kidney, and Cd accumulation in these organs. The severity of these changes was also related to the dietary level of B₆. Although the data offer supportive evidence that Cd toxicity impairs iron metabolism, the sparing effect of B₆ deficiency on Cd-induced anemia may be related to an influence of B₆ on Cd transport rather than to an effect of B₆ on iron homeostasis.