Effect of Fluorine on the Activity of Vitamin D in Rachitic Rats

Abstract
Summarizing, we have found: (1) In rats on a rachitogenic diet containing fluorine, there appears to be a decrease in the severity of the rickets due to a general increase in the density of the bones to x-rays and, more particularly, to a decrease in width of the metaphyseal zone of hypertrophic cartilage. (2) Vitamin D promotes the healing of this “fluorine rickets” but the deposition of new bone salt is atypical, its appearance suggesting that fluorine has in some way interfered with the orderly arrangement of the matrix cells. (3) Fluorine inhibits the healing process when given simultaneously with vitamin D to rachitic rats which have not been previously subjected to fluorine poisoning. This inhibition is roughly proportional to the dose given and amounts to 50% at a level of 3.0 mg. of fluorine per day.