[Kinetic characteristics of creatine kinase and hexokinase from rat skeletal muscles during dietary deficit of vitamin K and administration of pelentane].

Kinetic parameters of rat creatine kinase isozymes at different vitamin K supply and treatment with antivitamin K--pelentan have been determined. MM-isozyme (skeletal muscle) has selective sensitivity to the vitamin K deficit, while BB and MB-isozymes (brain, kidney and heart) have not. The value KM for ATP of MM-isozymes increases, while maximal activity decreases. Pelentan treatment does not lead to the change of MM-creatine kinase affinity to ATP. Soluble hexokinase of skeletal muscle in rats with vitamin K deficiency and treated with pelentan has higher affinity to glucose as compared to normal rat enzyme. It has been supposed that skeletal muscle hexokinase exists in a particular molecular form under vitamin K deficiency.