Inhibitory Effect of Riboflavin Tetrabutyrate on the Lipid Peroxidation by Pentachlorophenol

It is suspected that pentachlorophenol (PCP), used as an organochlorine herbicide, has toxicity related with the lipid peroxidation. The lipid peroxidation by the in vitro metabolism of PCP in a microsomal system was inhibited by riboflavin tetrabutyrate (B2-But), a fat-soluble riboflavin, but not inhibited by water-soluble flavins. The lipid peroxidation in the liver of mice exposed to 35 μmol/kg of PCP was suppressed by the simultaneous administration of B2-But, but scarcely suppressed by other flavins. Moreover, the changes of mitochondrial ADP/O ratio and flavin contents in the liver of mice were also suppressed by B2-But. It was considered that the suppressive effect of B2-But on the liver injury by PCP due to the inhibition of the lipid peroxidation and the flavin supply by B2-But in the liver.