Abstract
The present experiments were planned to demonstrate whether deposition of fluorine in bone can be prevented, or elimination of fluorine from the crystal surfaces of the bone mineral can be accelerated by injection of sodium citrate.
High level of fluorine (150 p. p. m. F.) was administered orally to group I albino rats, weighing 50-70g, together with injection of sodium citrate while to group II together with the injection of physiological saline. Althougher higher concentration of citrate in femurs was found in group I than that of group II, however, as to fluoride content no appreciable difference could be seen between the two groups.
To group III, distilled water was administered orally together with injection of sodium citrate. Consequently, group I was found to contain less citrate in femurs than group III. Namely, citrate ion competes with fluoride ion on the crystal surfaces of the bone mineral, and fluoride ion can replace citrate ion, however, citrate ion cannot take the place of fluoride ion, since both of them are charged negatively.
Following administration of high level of fluorine for seven days, fluoride ion seemed to deposite on bone to a certain extent, then sodium citrate was injected to group IV, and physiological saline to group V for five days. It was found that the citrate content in bones of group IV increased more than that of the group V, nevertheless, as to the fluoride content no appreciable difference could be seen between the two groups. The evidences obtained indicate that citrate ion does not displace already deposited fluoride ion in the mineral surfaces.
