Role of the dioxin-like toxic compound coplanar polychlorinated biphenyl,3,3′,4,4′,5-pentachlorobiphenyl in reducing hepatic alcohol dehydrogenase levels in rats in vivo

The ability of a dioxin-like toxic compound, coplanar polychlorinated biphenyl, 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) to reduce the protein level of hepatic class I alcohol dehydrogenase (ADH), which plays an important role in the metabolism of ethanol, was studied. Male Wistar rats received PCB126 25 mg/kg i.p. At this dose the compound induces a wasting syndrome. PCB126 administration resulted in a significant suppression of the protein level of class I ADH, whereas the difference between free- and pair-fed controls was slight. These results suggest that dioxins also reduce class I ADH without involvement of decreased food consumption. These data offer new insights into the toxicity of dioxins via a marked decrease in the level of class I ADH.