Detection of stable acetaldehyde-modified proteins in the livers of ethanol-fed rats

Liver cytosolic fractions, obtained from rats pair-fed diets supplemented with either ethanol or an isocaloric amount of sucrose for periods from 3 weeks to 27 months, were tested for the presence of acetaldehyde-modified proteins by immunoblotting, using a partially purified antiserum raised in rabbits against proteins modified by acetaldehyde in vitro. The antiserum reacted with a large number of proteins in cytosolic fractions from ethanol-fed rats but did not react with any proteins in the same fraction from control animals. The duration of the ethanol-containing diet did not appear to influence the number of proteins modified or the total amount of modification within the time range tested. These results indicate that many proteins in rat liver cytosol are targets for modification by acetaldehyde in vivo.