title: Vitamin K requirement and the concentration of vitamin K in rat liver.
abstract: The concentration of vitamin K was determined in the liver of different strains of rats, and in male and female warfarin-resistant rats by feeding 3H-vitamin K in a purified diet. In each case, the level of vitamin K in the liver correlated approximately with the amount of vitamin K fed. The results indicate that differences in the requirement for vitamin K between the sexes and between strains of rats are due principally to different required concentrations of vitamin K in liver and not to differences in absorption or turnover of the vitamin. The results of the determination of vitamin K epoxide levels in male and female warfarin-resistant rats, and other data, suggest that the amount of vitamin K required in liver may be in part due to differences in the activity of the enzyme, vitamin K epoxide reductase.
mesh_terms: D000818:Animals; D004351:Drug Resistance; D004988:Ethers, Cyclic / Q000378:metabolism; D005260:Female; D008099:Liver / Q000378:metabolism*; D008297:Male; D009751:Nutritional Requirements; D010088:Oxidoreductases / Q000378:metabolism; D051381:Rats; D012737:Sex Factors; D013045:Species Specificity; D014812:Vitamin K / Q000031:analogs & derivatives / Q000378:metabolism; D014859:Warfarin
chemical_list: D004988:Ethers, Cyclic; D014812:Vitamin K; D014859:Warfarin; D010088:Oxidoreductases