Role of Vitamin A in Induction of Vitamin K Deficiency in the Rat ∗

Abstract

Summary

Evidence is presented to indicate that the level of dietary Vit. A is closely related to development of symptoms of Vit. K deficiency in the rat. Under appropriate experimental conditions, 0.5 and 5 i.u. of Vit. A per gram of diet gave reduced prothrombin concentrations which were not observed on corresponding rations deficient in Vit. A. This extends the previously known hemorrhagenic toxicity of Vit. A to physiological levels and emphasizes the need for careful consideration of the level of Vit. A in studies of Vit. K deficiency in the rat. The effect of Vit. A was more severe in male than in female rats. In further studies with male rats, Vit. A acid was markedly more hemorrhagenic than Vit. A acetate.