Interrelationships Between Vitamin K and Estrogenic Hormones

Abstract

Evidence has been presented indicating a protective effect of estrogenic hormones in vitamin K deficiency. Female rats are more resistant to the development of dietary K deficiency than are male animals. This difference is most pronounced during early adulthood. Castration increases the susceptibility of the female rat and decreases that of the male rat to hypoprothrombinemia and hemorrhagic death during the feeding of vitamin K-deficient diets. In male animals fed similar diets, the injection of estrogens results in improved prothrombin levels and a lower mortality. Administration of testosterone has an opposite effect. A single large dose of the anticoagulant, warfarin sodium, is followed by a greater mortality due to hemorrhage in male rats than in female rats of the same age. In male animals some protection against the effects of the anticoagulant is afforded by pretreatment or by simultaneous administration of estrogenic substances. Effects considered to be characteristic of estrogenic hormones, for example, increases in the uterine weight and cornification of the vaginal epithelium in castrates, have been shown to follow the administration of both K₁ and menadione. With K₁, at least, paradoxical effects occur with increasing dose level or continued administration. When K₁ is administered concomitantly with estradiol, uterine weights are considerably decreased in comparison to those resulting from the same dose of estradiol given alone.