Abstract

The antiarrhythmic activity of fluoride was studied in a model of CaCL2-induced heart arrhythmias in male albino rats. The prolonged intake of sodium fluoride with drinking water (2 mg/l for 1 month) significantly reduced the severity of arrhythmias that was evident as an increase in the latency and a decrease in the frequency and duration of arrhythmias. A less pronounced effect was noted when the concentration of sodium fluoride was increased to 5 mg/l. At larger concentrations (11 mg/l) the fluoride exerted a toxic effect and potentiated the arrhythmogenic action of CACL2. The antiarrhythmic action of fluoride in low concentrations may be associated with the blockade of an inward Ca current.