[Dietary proteins and deiodination in the liver]

The authors studied in male Wistar rats the effects of diets containing 66 and 2% (w/w) of protein on the one hand, and 18% (w/w) of protein on the other hand, on the deiodination of L-thyroxine in liver homogenate supernatants. The deiodase activity in the liver protein increased in case of low-protein diet, and decreased in case of high-protein diet; these differences were statistically significant. When the body weights of the animals were taken into account, the deiodinating power of the whole liver was significantly reduced in case of low-protein diet, but not significantly reduced in case of high-protein diet. Consequently, the reference value adopted for the calculation of the degree of deiodination is of paramount importance to validity.