Effect of fluoride on the respiration rate of rat cardiac mitochondria.

Fluoride by modifying the activity of mitochondrial enzymes may change their respiration rate. In this study NaF at concentrations 5, 10, and 50 PM had no effect on the State 3 respiration rate of rat cardiac mitochondria with succinate substrate. At a higher concentration of 7.5 mM, a significant (p<0.001) decrease by as much as 120.4 +/- 5.7 nmol [O]/min/mg protein occurred in the State 3 respiration rate with succinate. Further increase in NaF concentration (15 and 25 mM) resulted in a reproducible decrease in the oxidation rate of the succinate in dose-dependent manner.