Abstract
A continuous daily administration of 20,000 I.U. of vitamin A or D to rats caused a decrease of body weight and led the animals to death at the advanced stage of the hypervitaminosis. By the heavy dose of vitamin A, levels of haemoglobin and erythrocyte were lowered at the early stage and then a temporary rise was observed, followed by a remarkable decrease at the advanced stage. Vitamin D had no effect on the haemoglobin level, but caused a gradual increase of erythrocyte number. Leucocyte number was also found to be small at the advanced stage in the vitamin A hypervitaminosis. In the case of vitamin D, an increase of leucocyte number was observed at the early stage, followed by a continuous decrease. In both cases, the changes of leucocyte number were found to be mainly those of lymphocyte number. A decrease of nuclear cell number occurred at the early stage of the vitamin A in the bone-marrow hypervitaminosis. After a temporary restoration, a gradual decrease was observed at the advanced stage. The changes were those of levels of erythroblast and granulocyte. On the contrary, in the vitamin D hypervitaminosis an increase of the cell number was observed at the early stage, followed by a gradual decrease. The changes in this case were found to depend mainly on those of erythroblast number.
