NEGATIVE EFFECTS OF VITAMIN K PREPARATIONS ON GLUCURONYL TRANSFERASE ACTIVITY
Keyword(s):
In vitro studies using a mouse liver microsome system failed to demonstrate that menadiol sodium diphosphate, menadione sodium bisulfite, or phytonadione enhanced or inhibited the quantity of ortho-aminophenol glucuronide produced. In vivo studies in young rats with these vitamin K analogues also failed to show an effect on glucuronide conjugation. Based on this data, it is concluded that the hyperbilirubinemia seen in prematures after large doses of water-soluble vitamin K analogues is probably not due to an inhibitory effect of glucuronyl transferase. The evidence suggesting that it may be due in part to hemolysis is briefly reviewed.