The Metabolism of Fluorine in the Rat Using F18 as a Tracer

Abstract

Radioactive tracer techniques using NaF tagged with F18 were employed to study the metabolism of inorganic fluoride in young adult and mature female rats at intervals up to 9 hours after administration. F18 was given orally and by vein in an essentially carrier-free state and with stable fluoride carrier. The deposition of Fl8 in the distal end of the femur 1 hour after administration was investigated radioautographically. Cell membranes appeared to be freely permeable to NaFl8. No significant deposition of F18 was noted in any of the soft tissues of the rat, except possibly in the kidney, and the deposition was not significantly affected by age. The distribution in the rat was essentially the same whether the Fl8 was given orally or by vein. Urinary excretion and skeletal deposition were similar whether the stable fluoride dose was 0.5 [mu]g/kg or 10 mg/kg. Radio-autographic and tracer data showed that the accumulation of Fl8 depended on the vascularity and growth activity of the bone.