Comparison of the Effect on Blood Coagulation Activity between Menaquinone-4 and Menaquinone-7 in Hypoprothrombinemic Rats Induced by Warfarin

Abstract

The restoring effect of MK-4 on the extrinsic coagulation activity was compared with that of MK-7 using hypoprothrombinemic rats induced by warfarin. With regard to oral administration, both MK-4 and MK-7 dose-dependently enhanced the coagulation activity, but the effect of MK-4 was observed more rapidly at 1 mg/kg body weight and more potently at all dosages examined than that of MK-7. In intravenous administration, the activity of MK-4 was the same as for oral administration. On the other hand, the concentration of MK-4 in liver was lower than that of MK-7 in both oral and intravenous administrations. These results suggest that MK-4 is more active than MK-7 in the production of vitamin K-dependent coagulation factors.