ラット精巣におけるビタミン K₁及びメナキノン-4投与後のビタミン K類の動態について

抄録

The investigation of vitamin K analogues (VKs) in animal body is difficult because of its low concentration. Recently we found that rat testis contains considerable high concentration of VKs. There are consisted with small quantity of phylloquinone (K₁) , menaquinone (MK) -6 and large quantity of MK-4 (20.70±5.05ng/g) . In this study, the chronological changes in the amount of VKs in the testes of rats by oral administeration of K₁ or MK-4 (1×10^-5mol/kg body weight) were measured. In K₁ administered group, the amount of K₁ increased at first, followed by K₁ decrease and MK-4 increase. In MK-4 administered group, the amount of K₁ does not change, keeping the same small amount as the controul group, but only the MK-4 amount increased. These results indicate that K₁ is rapidly changed to MK-4, so that MK-4 may be the biological from in the body.