Modulation of Fluoride Toxicity in Rats by Calcium Carbonate and by Withdrawal of Fluoride Exposure

Abstract

In order to assess the effect of calcium on the toxic effects of fluoride, adult female Wistar rats were treated with sodium fluoride (NaF, 500 ppm in drinking water) alone or in combination with calcium carbonate (CaCO 3 , 50 mg/ kg by oral intubation) daily for 60 days. Food, water and fluoride intake were measured daily for 60 days. Body weight gain, exploratory motor activity, rota-rod motor coordination, dental structure, activities of acetylcholinesterase (AchE, brain and skeletal muscle) and Na π K π ATPase (erythrocyte membrane and skeletal muscle) and the concentrations of protein (serum and skeletal muscle), calcium (serum) and fluoride (serum) were determined in these animals 24 hr after the last treatment. The same parameters were tested in another group, 60 days after withdrawal of NaF exposure (500 ppm in drinking water daily for 60 days). NaF treatment decreased food and water intake, reduced body-weight gain and impaired exploratory motor activity and rota-rod performance. Dental lesions, inhibition of the activities of AchE and N π K π ATPase and a decrease in the concentration of protein, and serum calcium were also observed in these animals. These effects were accompanied by a marked elevation of fluoride concentration in the serum. CaCO 3 decreased the concentration of fluoride in the serum of NaF-treated animals. A decrease in serum fluoride concentration was found also after NaF withdrawal. A prevention of locomotor behavioural, biochemical and dental toxicities of fluoride was observed both in these groups. It is concluded that the dose of CaCO 3 used in the present study has a potential to prevent the toxicity of fluoride by maintaining serum fluoride at a less toxic level. Further, the toxic effects of fluoride are reversible if its exposure is withdrawn for 2 months.

Effect of Boron as an Antidote on Dry Matter Intake, Nutrient Utilization and Fluorine Balance in Buffalo (Bubalus bubalis) Exposed to High Fluoride Ration

“…Similar findings were reported by many researchers in different farm animals affected with chronic F toxicity [31][32][33]. Increased serum fluoride level caused alterations in the production of certain metabolites that caused depression in appetite [9], and this might be the probable reason for lower DMI on high F intake in the calves. Improvement in DM intake elucidates the antidotal effects of boron in the calves fed high fluoride ration, since boron has modified F effect possibly because of decreased absorption and retention of dietary F in the body.…”

“…The major clinical signs of chronic fluorosis in bovines include dental discoloration, mottling of teeth, bony exostosis, lameness, and debility [7,8]. Increased fluoride level in the blood causes alterations in the production of certain metabolites that leads to depression in appetite [9]. Attempts have been made in the past to combat F toxicity through prevention of F absorption or enhancing its excretion from the body with various feed supplements.…”

Qualidade seminal e histomorfometria dos órgãos reprodutivos de ovinos tratados com fluoreto de sódio

“…Esse elemento se liga ao F e atua como antídoto, formando complexos insolúveis (EKAMBARAM & PAUL, 2002;ZHOU et al, 2007). No estudo realizado por CHINOY et al (1997) em ratos, foi efetuado inicialmente o tratamento com NaF (10mg kg -1 de peso corporal), durante 30 dias e, subseqüentemente, tratamento com fosfato de cálcio (62,5mg animal -1 dia -1 ), durante o mesmo período.…”

Evaluation of vitamin E and calcium effects on fluoride toxicity-induced fertility impairment

“…Ekambaram and Paul (2002) concluded that calcium carbonate prevented the toxicity of Fl by maintaining serum Fl at a less toxic level. In addition, the toxic effects of Fl are reversible if exposure is withdrawn for 2 months.…”

“…They were administered NaF for 60 days. Rats were then maintained on calcium (Calcium gluconate ampoules, MEPACO, Egypt) (50 mg kg À1 day À1 orally) (Ekambaram and Paul 2002) for a further 60 days. (d) Group V consists of 10 rats.…”