Dietary selenium and levels of L-ascorbic acid in the plasma, livers, and lungs of polychlorinated biphenyls-treated rats.

Administration of polychlorinated biphenyls (PCB) (500 mg Aroclor, 1254/kg body weight) intraperitoneally significantly increased the levels of L-ascorbic acid in the plasma and livers, but not in the lungs of one-month-old male rats maintained on a basal low selenium diet with or without 2.0 ppm selenium (as sodium selenite) supplementation for 19 weeks prior to PCB treatment. The levels of L-ascorbic acid were not significantly altered by dietary selenium. In another experiment, 40 days or 15-month-old male rats were fed the same basal selenium diet with or without 1.0 ppm selenium for 1 month prior to PCB treatment. The plasma levels of ascorbic acid were found to increase significantly by PCB treatment, but not by the status of dietary selenium or by animal age. As expected, the activity of selenium dependent glutathione peroxidase was markedly decreased in the plasma, livers, and lungs of rats fed the low selenium diet. However, the enzyme activity was not significantly altered by PCB treatment in plasma, livers, and lungs of animals in both dietary groups.