METHIONINE TOXICITY IN RATS EXPOSED TO COLD

Abstract

Male rats of the Wistar strain were fed a control diet (20% casein) and the same diet to which 3% DL-methionine was added, at environmental temperatures of 24 and 7 °C. Effects of methionine feeding at 24 °C were hypophagia, reduced body weight gain, increased kidney weight, decreased liver weight, deposition of iron in the spleen, and paleness of the eyes; there was no effect upon liver fat concentration. At 7 °C, food (and hence methionine) intake was markedly increased in rats fed the methionine-supplemented diet; the accentuation of effects of methionine feeding in these animals might be attributable to the increased intake of this amino acid. In addition, a condition resembling severe frostbite of the ears and paws was observed in these animals. From the results of this experiment it is apparent that the catabolic effect of cold exposure does not eliminate the deleterious effect of excess dietary methionine.