[Activity of menadione reductase and level of cytochrome B5 and P-450 in liver with varying supplies of vitamin K and administration of pelentan to rats].

Content of cytochromes b5 and P-450 as well as activity of soluble menadione reductase were estimated in liver microsomes of rats deprived of vitamin K or maintained both on a diet containing excess of vicasol or antivitamin K-pelentan. Deficiency of vitamin K led to an increase in the specific activity of menadione reductase and in content of the cytochrome P-450. Administration of antivitamin K did not alter these parameters but caused an increase in the content of cytochrome b5, which was not changed in vitamin K deficiency. Dissimilar effects of alimentary deficiency in vitamin K and of pelentan administration suggest that administration of antivitamins K (although it allowed to discover alterations developed via the system of vitamin K-dependent carboxylation) could not be completely identified with alimentary vitamin K deficiency.