The distribution of CO58-labeled vitamin B12 in the rat with fatty metamorphosis and cirrhosis of the liver

Abstract 1.1. The distribution pattern of Co 58 -cyanocobalamin, mainly in kidney and liver, has been studied in the normal rat and the rat with fatty metamorphosis and cirrhosis of the liver. 2.2. The fatty and cirrhotic liver has been found to have a diminished binding capacity for Co 58 -cyanocobalamin. The data suggest that this binding capacity is more severely impaired in the fatty than in the cirrhotic liver. 3.3. In the normal rat, the concentration of administered Co 58 -cyanocobalamin in the liver increases gradually and reaches a maximum around the fourteenth day; in the fatty liver the concentration is smaller on the fourteenth than on the second day. 4.4. The kidney of the animals with fatty metamorphosis and cirrhosis of the liver has been shown to have an increased binding capacity for Co 58 -cyanocobalamin. In the normal kidney, the Co 58 -cyanocobalamin concentration diminishes between the second and fourteenth days following the administration of the labeled vitamin. In contrast, the kidney of the animal with fatty metamorphosis of the liver maintains or increases its Co 58 -cyanocobalamin content during this period. 5.5. It is suggested that the diminished binding capacity of the damaged liver leads to the utilization of other potential binding sites for the vitamin, especially the kidney.