Effect of ethanol on the in vivo covalent binding and in vitro metabolism of aflatoxin B1 in rats

Abstract

The binding of [ 3 H]aflatoxin B 1 (AFB 1 ) to the DNA, RNA and protein of liver after i.p. administration to rats with and without ethanol pretreatment was studied. The quantities of afb 1 binding to DNA and RNA were significantly increased by ethanol pretreatment but the formation of protein adducts was not affected. AFB 1 metabolism by hepatic microsomes from ethanol-treated rats to aflatoxins m 1 (AFM 1 ) and Q 1 (AFQ 1 ) was increased when compared to those of control microsomes. These results suggest that an increase in AFB 1 binding to liver nucleic acids and AFB 1 metabolism after pretreatment of ethanol resulted from an increase in hepatic mixed-function oxidases and a possible decrease in hepatic glutathione (GSH) content which subsequently lead to an increase in hepatotoxicity of AFB 1 . © 1986.