Effects of intermittent exposures of aflatoxin B-1 on hepatic and testicular glutathione S-transferase in rats

Glutathione S-transferase (GST) plays a major role in the detoxification of the potent hepatocarcinogen aflatoxin B-1 (AFB(1)). This study evaluated t he effects of intermittent exposures to AFB(1) on hepatic and testicular GS T in rats. Male Fischer 344 rats were fed diets containing APE, (0, 0.01, 0 .04, 0.4 and 1.6 ppm) intermittently at 4-week intervals up to 20 weeks. Th e control animals were fed an AFB(1)-free NIH-31 diet. Rats consuming diets with 0.01 ppm AFB(1) did not show the induction of hepatic or testicular G ST activity. Intermittent exposures to AFB(1) at concentrations of 0.04-1.6 ppm significantly increased the GST activities. The increase of the enzyme activity was proportional to the dose and length of AFB(1) exposure. Copyr ight (C) 2000 John Wiley & Sons, Ltd.