Abstract
Acute fluoride intoxication increases intracellular calcium (Cai), manifested by increased twitch tension in cardiac muscle, and by potassium efflux (mediated by Ca2+-dependent K+ channels) in fluoridated erythrocytes. Fluoride, like isoproterenol, stimulates adenylate cyclase, and could increase Cai via the effects of cAMP on Ca2+ channels. However, while the inotropic effects of fluoride mimicked isoproterenol in rat atria, their effects on the time course of isometric contraction were quite different. In addition, acetylcholine negated isoproterenol’s effect on twitch tension but did not modulate the effects of fluoride. Further, the Ca2+ channel antagonist verapamil had no effect on fluoride-stimulated K+ efflux from erythrocytes. Fluoride also inhibits Na+-K+ ATPase, and increases intracellular Na+, so could increase Cai via Na+-Ca2+ exchange. Lanthanum, which blocks Na+-Ca2+ exchange, blocks fluoride-induced K+ efflux in erythrocytes. We conclude that the effects of fluoride on adenylate cyclase are not important in intact tissue, and that inhibition of Na+-K+ ATPase and subsequent Na2+-Ca2+ exchange may be the mechanism of increased Cai in acute fluoride toxicity.
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Fluoride in Drinking Water: A Scientific Review of EPA’s Standards.
Excerpts: Summary Under the Safe Drinking Water Act, the U.S. Environmental Protection Agency (EPA) is required to establish exposure standards for contaminants in public drinking-water systems that might cause any adverse effects on human health. These standards include the maximum contaminant level goal (MCLG), the maximum contaminant level (MCL), and the secondary
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Interactive effect of arsenic and fluoride on cardio-respiratory disorders in male rats: possible role of reactive oxygen species.
Epidemiological evidence demonstrates positive correlation between environmental and occupational arsenic or fluoride exposure and risk to various cardio-respiratory disorders. Arsenic-exposure has been associated with atherosclerosis, hypertension, cerebrovascular diseases, ischemic heart disease, and peripheral vascular disorders, whereas Fluoride-exposure manifests cardiac irregularities and low blood pressure (BP). Present study aims to study
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Oxidative indices correlate with dyslipidemia and pro-inflammatory cytokine levels in fluoride-exposed rats
The aim of this study was to establish the effects of fluoride on lipid metabolism and attendant inflammatory response by exposing rats to 50 mg L-1 and 100 mg L-1 of fluoride through drinking water for seven weeks. Both concentrations led to hypercholesterolemia while the 100 mg L-1 concentration induced
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Fluoride stimulation of slow Ca2+ current in cardiac muscle.
Fluoride, a known activator of the adenylate cyclase in broken-cell preparations of heart and other tissue [21, 22] was tested for its ability to act as a positive inotropic agent in cardiac muscle and for its ability to concomitantly induce Ca2+ channels. The induction of slow Ca2+ channels was tested
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Effects of melatonin and epiphyseal proteins on fluoride-induced adverse changes in antioxidant status of heart, liver, and kidney of rats
Several experimental and clinical reports indicated the oxidative stress-mediated adverse changes in vital organs of human and animal in fluoride (F) toxicity. Therefore, the present study was undertaken to evaluate the therapeutic effect of buffalo (Bubalus bubalis) epiphyseal (pineal) proteins (BEP) and melatonin (MEL) against F-induced oxidative stress in heart,
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Fluoride & Arteriosclerosis
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, Blood Pressure and Hypertension
Individuals with blood pressure readings that exceed 140/90 are considered hypertensive. Hypertension can increase the risk of stroke, heart attack, heart failure, aortic aneurysms, and peripheral arterial disease. An association between increased fluoride in ground water and increased prevalence of hypertension has been observed, especially among adult males (Amini et
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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 & 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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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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