Abstract
The modulatory actions of fluoride on the function of the dihydropyridine-sensitive (L-type) Ca2+ channel were studied in rabbit cardiac myocytes. In cell-attached voltage-clamp experiments, using barium as the charge carrier, fluoride increased the activity of the Ca2+ channel dose-dependently. Low concentrations (<10 mM) of fluoride increased the number of traces with channel activities, and decreased the number of traces without channel activities, resulting in a net increase in the open-channel probability. The effect of 5 mM fluoride on the Ca2+ channel was inhibited by the presence of non-hydrolyzable guanosine diphosphate analog in the cell. On the other hand, high concentrations (>10 mM) of fluoride increased the open-channel duration, resulting in a marked increase in open-channel probability. A pretreatment of myocytes with a phosphatase inhibitor, okadaic acid, virtually abolished the additional effect of fluoride on the open-channel duration or open probability. A concentration of up to 75 mM fluoride had no effect on the Ca2+-channel activity when the myocytes were pretreated with a potent inhibitor of protein kinases, indicating that fluoride increased the Ca2+- channel activity via modulation of the phosphorylation state of the myocyte or the channel protein alone.
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Medical aspects of excessive fluoride in a water supply
A 10-year study of 116 persons in Bartlett and 121 in Cameron, Tex., was conducted to determine if prolonged exposure to fluoride in the water supply of Bartlett had produced detectable physiological effects. Bartlett's water contained about 8 p.p.m. F until 1952, when an experimental defluoridation unit was installed, reducing the
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Analysis of x-ray heart areas of 30 patients with endemic fluorosis
I. Targets and methods Based on diagnosis standards formulated at the 1981 Shijiazhuang National Prevention of Endemic Fluorosis Meeting, 30 patients were chosen, 15 men and 15 women with an average age of 45, average height of 1.63 meters, and average weight of 54 kilograms, and all with clinical diagnoses
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Indoor air quality and health: Empirical evidence from fluoride pollution in China.
Highlights Burning high-fluoride-content coal indoors is the primary source of fluoride pollution in Guizhou Province of China. We apply individual fixed effect models to examine the effects of whether households use coal as domestic fuel. Fluoride pollution from coal burning significantly increases the blood pressure levels and the likelihood of
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Effects of chronic fluorosis on electrocardiogram in sheep
This study was carried out to evaluate the effects of chronic fluorosis by means of the electrocardiograms in sheep. Ten sheep with fluorosis living around a volcanic mountain (Tendürek Mount) in East Anatolia in Turkey and 10 healthy sheep were used. Leads I, II, III, aVR, aVL, aVF, V2, V4,
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Fluoride and calcium levels in the aorta
Among soft tissue organs which store fluoride (F-), the aorta contains the highest levels. [1-2]. Calcifications of arteries of the Monckeberg type have been reported in relatively young persons afflicted with skeletal fluorosis from endemic areas. [3-5] It was, therefore, of interest to determine whether or not there is a
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Fluoride & Myocardial Damage
Structural damage to the heart resulting from fluoride toxicity has been observed in numerous human and animal studies. The general features of this damage include cloudy swelling, vacuolization or vacuolar degeneration, hemorrhages, interstitial edema, fibrous necrosis, dissolution of nuclei, and thickening of the vessel walls in the heart muscle (Basha
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Fluoride & Arterial Calcification
The major change involved with cardiovascular disease is development of atherosclerosis in critical arteries, which is partially characterized by vascular calcification. The level of coronary artery calcification is thought to be the most important indicator of future cardiovascular events. Increased arterial calcifications have frequently been reported in those with skeletal fluorosis
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Healthy arteries are flexible and elastic, allowing efficient transfer of blood and nutrients from the heart to the rest of the body. Arteriosclerosis refers to a stiffening of the arteries, including loss of elasticity. This is a slow, progressive disease that may begin early in life from damage to the
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Fluoride & Electrocardiogram Abnormalities
An electrocardiogram (ECG) is a diagnostic test that measures the electrical activity of the heart. An ECG can reveal heart rate, heart rhythym (i.e. steady or irregular), and the strength and timing of the heart’s natural electrical signals. ECGs are described in terms of “waves” (e.g. amplitude and duration). Problems
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