Abstract

Since fish hearts are resistant to the effects of hypoxia, comparison of the effects of hypoxia and ischaemia on fish and mammalian hearts may lead to better understanding of ischaemic injury in mammalian hearts. The ultrastructure and levels of ATP, creatine phosphate, and lactic acid were examined in hearts obtained from largemouth bass. Bass hearts were subjected to conditions of normoxia, ischaemia, hypoxia, and hypoxia in the presence of fluoride and cyanide. ATP levels remained stable during hypoxia and ischaemia, but fell during hypoxia in the presence of fluoride or fluoride plus cyanide. Changes in creatine phosphate and lactic acid indicated ATP was produced during hypoxia and ischaemia by glycolysis, by rephosphorylation from creatine phosphate, and by oxidative phosphorylation with oxygen obtained from myoglobin or the atmosphere. Ultrastructural changes were found similar to those reported in ischaemic mammalian heart, consisting of inter- and intracellular swelling, glycogen depletion, and mitochondrial alterations. Comparison of metabolic rates between fish and mammalian hearts suggests the lower rate in fish hearts may be the chief factor which permits stable ATP levels during hypoxia and ischaemia, and thus provides resistance to these conditions.

• Related Studies :

  • Cardiopulmonary response to sodium fluoride infusion in the dog

    Because humans are occasionally acutely exposed fluoride (F-), and cardiac and especially pulmonary to high levels of tissue accumulate higher concentrations of F- than do the other soft tissues, the present study was undertaken to investigate the effects of acute exposure to toxic plasma levels of F- on cardiopulmonary hemodynamics. Anesthesized

  • Histological and chemical studies in man on effects of fluoride

    The presence of elevated concentrations of fluorides in the atmosphere has been associated with changes in certain plants and an increase in the fluoride content of forage in certain areas in Utah. Long-term ingestion of such forage by some animals has produced changes characteristic of fluorosis in some of them.

  • Sodium fluoride induces apoptosis in H9c2 cardiomyocytes by altering mitochondrial membrane potential and intracellular ROS level

    Chronic excessive fluoride intake is known to be toxic, and effects of long-term fluorosis on different organ systems have been examined. However, there are few studies about the effects of fluorosis on cardiovascular systems. Here, we studied the fluoride-induced apoptosis in H9c2 cells and determined the underlying molecular mechanisms including

  • 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

  • The influence of fluoride ions upon selected enzymes of protein metabolism in blood plasma of rabbits with hypercholesterolemia

    Three-month studies were performed on 18 adult rabbits of New Zealand breed divided into three groups, with six animals in each: a control group on standard diet, a cholesterol group receiving 500 mg of cholesterol/100 g of feed per rabbit per 24 h (CH group), and a cholesterol + fluorine

• Related FAN Content :

  • 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

  • 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

  • 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

  • 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

  • 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