EFFECTS OF VITAMIN-K-1 AND MENADIONE ON ETHANOL-METABOLISM AND TOXICITY

The effect of administration of two exogeneous quinones on in vivo eth anol metabolism and ethanol-induced toxicity has been investigated. Me nadione (vitamin K-3; 50 mg/kg) or vitamin K-1 (250 mg/kg) were given subcutaneously (sc) to male Sprague Dawley rats 1 hour before oral adm inistration of ethanol (4 gm/kg). Menadione, a good quinone reductase substrate, increased the elimination rate of orally administered ethan ol thereby decreasing its bioavailability (as measured by the area und er the curve (AUC) relating blood level to time) and its induced hepat ic triglyceride accumulation. On the other hand, closely related struc tural analog, vitamin K-1, which was proven to be a poor substrate for quinone redtuctase, failed to show any significant effect. Thus, thes e results suggest that quinone reductase appear to play a role in in v ivo ethanol metabolism and toxicity.