Comparison of 131-I retention in the plasma of rabbits fed toxic quantities of cupric or molybdate ions as supplements to a commercial pelleted diet or to an oats-alfalfa laboratory diet.

Abstract

The retention of 131I in the protein-free plasma of rabbits fed a commercial diet has been reported previously. In the present study an attempt was made to defeat this retention by feeding or by intramuscular injection of cupric acetate solution. Copper did not reverse the retention; conversely, copper was more effective in producing the retention than was molybdate. The effect of copper plus molybdate was not cumulative, nor did one ion appear to reverse the retention caused by the other. Acute starvation produced a more extensive 131I retention than did highly toxic levels of copper. 131I retention was also observed for rabbits fed an oats–alfalfa laboratory diet even in dietary groups receiving no added molybdate or copper. Seventy-two hours after the injection of 131I, the oats–alfalfa control groups showed a 131I concentration in protein-free plasma approximately 50 times that of control rabbits fed the commercial diet. The common factor in the 131I retention is believed to be relative partial starvation because of nutritional deficiency or lack of palatability of the diet, or the fact that the rabbits became too ill to eat normal quantities of food.