[In vitro study on effect of body weight on deiodination of L-diiodotyrosine and L-thyroxine in liver and kidney of rats on standard diets].

The effect of body weight on the deiodination of L-di-iodotyrosine and L-thyroxin in the liver and kidney was studied in vitro in male Wistar rats of same age, but differing in weight (light and heavy, respectively), which were fed a standard diet. In the livers of the heavy animals, the deiodination of L-di-iodotyrosine and L-thyroxin was significantly lower than in those of the light animals. As to the kidneys, no such difference was observed. From a comparison with literature data it is concluded that the reduction in deiodination in the livers of the heavy animals might be due to a reduction in thyroid hormone metabolism.