Inhibition of three glycolytic enzymes by NaF and Na2PO3F? in isolated rat hepatocytes has been demonstrated. The data indicate that incubation of hepatocytes with NaF or MFP and subsequent removal of NaF and MFP results in a significant inhibition of enolase (E.C. 126.96.36.199), phosphoglucomutase (E.C. 188.8.131.52.), and pyruvate kinase (E.C. 184.108.40.206). It is suggested that the fluorine compound enters the hepatocyte, becomes bound to the enzyme (phosphoglucomutase and enolase) and inhibits its activity. The inhibition of pyruvate kinase may be due to a cAMP dependent phosphorylation of the enzyme.
The effects of fluoridated water on rat urine and tissue cAMP levels
Male Wistar rats were fed a fluoride deficient diet (less than 0.5 parts/10(6) F), and either distilled water or fluoridated water (1.0 parts/10(6)). By week 3, the control group had urinary excretions of 106 +/- 5 nmol cAMP/day (mean +/- SEM) whereas the experimental group excreted 129 +/- 6 nmol
Fluoride inhibition of rat liver microsomal esterases
Fluoride inhibition of a purified rat liver microsomal esterase was investigated using the substrates phenyl butyrate and ethyl butyrate. The data are consistent with EHF --EH -- EdES -- products where S, E, EH, and EHF are substrate, active enzyme, protonated enzyme (inactive), and an inactive enzyme-fluoride complex, respectively. Fluoride
In vivo influence of sodium fluoride on sperm chemotaxis in male mice
Reproductive process covers lots of procedures, including capacitation, hyperactivation, chemotaxis and the acrosome reaction. Each plays an important role in the success of fertilization. Although multiple studies have reported the toxic effects of fluoride on the male reproduction, the effect of fluoride on sperm chemotaxis is little known. This study
Influence of extended exposure to sodium fluoride and caffeine on the activity of carbohydrate metabolism enzymes in rat blood serum and liver.
A 50-day study of the influence of fluoride (F) and caffeine on carbohydrate metabolism enzymes was conducted on 18 male Sprague-Dawley rats, 4.5 months old, housed in separate cages at 22–25°C on a 12-hr light/dark cycle. The rats were divided into three groups with six rats in each group: control,
Comparison of the effects of various agents on thyroidal adenyl cyclase activity with their effects on thyroid hormone release
Intact mouse thyroid glands were used to measure the formation of cyclic [3H]AMP from [3H]adenine, and the release of thyroidal iodine. These two parameters of thyroid activity responded to similar concentrations of thyroid-stimulating hormone (TSH). Both were stimulated by prostaglandin E1, although the response was always very much less than
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