Abstract

Five-day-old Wistar rats were given three intraperitoneal injections at 2-hourly intervals of a solution of sodium fluoride in 0.9 per cent sodium chloride. Three fluoride levels were used: a mottling dose of 3 mgF/kg body weight; and two sub-mottling doses, 0.05 mg and 0.01 mgF/kg body weight. Thirty minutes after the last injection, each rat received 5 ?Ci/g body weight of [³H]-serine. The design allowed for within-litter comparisons of treatments to be made. Rats were killed 1 hr and 20 hr after the injection of the label, and the tissues were processed for light microscope autoradiography.

After 1 hr, there was a reduced uptake with the mottling dose and an increased uptake with the smaller sub-mottling dose of fluoride. However, there was not a uniformly parallel pattern at 20 hr.

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