Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cardiomyopathic hamsters (UM-X7.1) show clinical signs of congestive heart failure and an abnormal EKG pattern. The sarcolemmal fraction obtained from the failing hearts at advanced stages of myopathy exhibited no change in the basal adenylate cyclase activity; however, the activity of this enzyme in the presence of catecholamines or NaF was lower in the failing heart sarcolemma than that in the control. The activities of Ca2+-ATPase, Mg2+-ATPase, and Na+-K+-ATPase in the failing heart sarcolemma were also less than the control values. These results suggest an association of membrane defect with heart failure.
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PMID:Membrane alteration in failing hearts of cardiomyopathic hamsters. 12 77

Sarcolemmal Ca++-ATPase, Mg++-ATPase, and (Na+-K+)-ATPase activities were increased in late stages of heart failure in myopathic hamsters (BIO 14.6) without any changes in the adenylate cyclase activity. On the other hand, these hamsters at early and moderate stages of heart failure showed depressions in mitochondrial calcium binding and uptake and microsomal calcium binding. Sarcolemmal (Na+-K+)-ATPase was decreased in failing hearts because of substrate lack, oxygen lack, and perfusion with Ca++-free, Na+-free, or K+-free medium. Both Mg++-ATPase and Ca++-ATPase activities of sarcolemma did not change on perfusing the hearts with substrate-free, hypoxic, Na+-free, or K+-free medium. Adenylate cyclase activity decreased on substrate-free or Ca++-free perfusion. Intracellular calcium overload produced by perfusing the hearts with medium containing calcium after Ca++-free perfusion was associated with decrease in all the sarcolemmal-bound enzyme activities. All types of failing hearts employed in this study showed a dramatic shift in the electrolyte composition. Failure of the cardiac muscle to generate contractile force on treatment with trypsin was associated with defects in the functions of sarcolemma, mitochondria, and sarcoplasmic reticulum, whereas such an effect on treatment with phospholipase C was limited to alterations in the activities of sarcolemma. The data suggest that abnormality at the level of sarcolemma plays an important role in the pathogenesis of heart dysfunction; however, the degree and direction of alterations in the sarcolemmal functions seem to be dependent upon the type of heart failure.
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PMID:Role of sarcolemmal changes in cardiac pathophysiology. 13 Jun 63

A study of myosin extracted from dog's cardiac muscle at different stages of chronic heart failure (from 1 week to 1 year) was carried out. A decrease of UV-luminescence intensity, flow birefringence and ATPase activity (to 70%) was observed. The electron microscopic investigation of myosin and LMM structure shows the loss of ability to form typical paracrystals by LMM, the electron microscopic appearance of the whole myosin being unchanged.
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PMID:[Structural and functional changes in myosin in chronic coronary insufficiency]. 13 86

We studied hearts from sham-operated and uninfected catheterized rabbits as well as from rabbits at early and late stages of cardiomyopathy and failure after 3 and 6 days of infection with Streptococcus viridans. No ultrastructural abnormalities or biochemical changes in membrane and myofibrillar activities were seen in 3-day uninfected hearts. In 6-day uninfected hearts there were decreased sarcolemmal M2+ ATPase, Na+-K+ ATPase, adenylate cyclase and calcium binding, microsomal calcium binding and uptake, and myofibrillar Ca2+-stimulated ATPase as well as increased mitochondrial calcium uptake. Slight ultrastructural changes also were apparent in 6-day uninfected hearts. At both early and late stages of infective cardiomyopathy and failure there were varying degrees of depression in sarcolemmal Mg2+ ATPase, Na+-K+ ATPase, adenylate cyclase and calcium binding, microsomal calcium binding, calcium uptake and basal ATPase, and myofibrillar Ca2+-stimulated ATPase activities. However, sarcolemmal Ca2+ ATPase and myofibrillar Mg2+ ATPase activities were decreased only after 6 days of infection. Mitochondrial calcium binding and uptake were increased in early stages but decreased in late stages of disease. Furthermore in infected hearts there were defects in mitrochondrial respiration and phosphorylation. Generalized severe myocardial cell damage involving myofibrils, mitochondria, and the sarcotubular system was seen only in late stages of infection. The results demonstrate impairment of different membrane and contractile protein functions as well as ultrastructural abnormalities in bacterial cardiomyopathic hearts which were absent or of lesser magnitude in hearts with only hypertrophy. The findings reported here suggest to use that there is an association between heart failure and changes in function of cellular components during bacterial infective cardiomyopathy.
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PMID:Abnormalities in heart membranes and myofibrils during bacterial infective cardiomyopathy in the rabbit. 13 11

1. The activities of some membrane-bound enzymes such as adenylate cyclase, Na+ + K+-stimulated adenosine triphosphatase (Na+ + K+-ATPase), Ca2+-stimulated ATPase and Mg2+-stimulated ATPase were examined in heart sarcolemmal fractions from control and cardiomyopathic hamsters at different stages of heart failure. 2. The basal adenylate cyclase activity in sarcolemma from cardiomyopathic animals with early, moderate and late stages of heart failure was not different from the control values whereas the sodium fluoride- and catecholamine-stimulated adenylate cyclase activities were depressed in cardiomyopathic sarcolemma at moderate and late stages. 3. The sarcolemmal Na+ + K+-ATPase activity was decreased and the non-specific phosphatase activity was increased at early, moderate and late stages of heart failure. 4. The sarcolemmal Ca2+-ATPase activity was decreased at moderate and late stages whereas the Mg2+-ATPase activity was decreased at the late stages of heart failure only. 5. A marked decrease was found in calcium binding by heart sarcolemma from cardiomyopathic hamsters at late stages of failure. 6. These results suggest that dramatic sarcolemmal changes are associated with heart failure, and support the view that membrane abnormalities play a crucial role in the development of myocardial dysfunction, cyclase, calcium binding, heart failure, heart membranes, sarcolemmal enzymes.
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PMID:Comparison of heart sarcolemmal enzyme activities in normal and cardiomyopathic (UM-X7.1) hamsters. 13 61

A study of the sarcolemmal Na+K+ATPase in the left failing heart due to induced mitral insufficiency was made in dogs. The sarcolemmal Na+K+ATPase markedly increased in the failing left ventricle. There was no change in the ATPase in the nonfailing right ventricle of the same dog. It was observed that during the early period of mitral incompetence, when there was an increase in the index of myocardial contractility, there was also a decrease in the sarcolemmal Na+K+-ATPase activity. There was no change in the MPG++-ATPase of the sarcolemmal fractions of either the failing or nonfailing ventricle. These results indicate that sarcolemmal Na+K+-ATPase appears to be involved in the reduction of the myocardial contractility during heart failure.
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PMID:Myocardial sarcolemmal ATPase in dogs with induced mitral insufficiency. 13 98

The Ca2+-activated myosin ATPase and the amino acid compositions of actin and myosin were determined for preparations from chronically failing dog hearts. Hypertrophy and congestive heart failure were produced by combined tricuspid valve insufficiency and pulmonary artery stenosis. Control, shamoperated, and noncardiac circulatory failure (inferior vena cava constriction) dogs also were studied. All hearts were divided into right ventricle, septum and left ventricle and each sample was individually analyzed. Calcium-activated ATPase decreased in the failing hearts and showed a distinct gradient of depression from right to left ventricles. There were no changes in ATPase activity among the other groups. The amino acid composition of actin was the same regardless of origin. The amino acid composition of myosin was unaltered except that cystine/2 residues were markedly decreased in failing heart myosin. The same gradient of depression was present as was found for Ca2+-activated myosin ATPase. This study suggests that protein metabolism is abnormal and that altered proteins are produced in hypertrophy and congestive heart failure. It appears that these changes do not affect all proteins, since actin was normal by the parameters studied. It is clear that the stressed ventricle is the most severely involved, but the entire heart is altered to some degree. Thus, we conclude that altered protein metabolism may be an important primary factor in the genesis of heart failure.
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PMID:The amino acid composition of actin and myosin and Ca2+-activated myosin adenosine triphosphatase in chronic canine congestive heart failure. 13 12

The effects of gramnegative endotoxin-induced myocardial failure in the pentobarbital-anesthetized dog were examined by monitoring its influence on cardiac myofibrillar ATPase activity. Myofibrils were isolated from endo- and epicardial portions of the left ventricular wall. ATPase activities were determined in animals treated with 4 mg/kg endotoxin and monitored 5 h, in animals monitored for 5 h without endotoxin (controls), and in animals implanted with a unilateral femoral shunt and given endotoxin. No differences were seen in the activities between the endo- and epicardial portions of any preparation. Activity was significantly depressed in endotoxemic animals. Increasing venous return by 313 +/- 71 ml/min significantly increased coronary flow by reducing coronary vascular resistance and prevented any observed depression of myofibrillar ATPase activity. In in vitro studies, adding endotoxin directly to a myofibril preparation did not modify normal activity. It appears that the mechanical and myofibrillar dysfunctions are due to the action of endotoxin at sites not associated with the actomyosin ATPase, but may be due to the production of an intermediary agent in concert with a decreased venous return.
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PMID:Endotoxin and myocardial failure: role of the myofibril and venous return. 15 Jul 99

Changes in cardiac metabolism in myocardial failure and after alcohol ingestion are discussed. The main effect of alcohol ingestion is loss of cardiac contractility. Since heart muscle does not contain alcohol dehydrogenase, its toxicity is probably the result of a direct toxic effect of ethanol and acetaldehyde on the myocardial cell, possibly involving various membrane systems. Alcohol inhibits mitochondrial respiration and the activity of enzymes in the tricarboxylic acid cycle, and its interferes with both mitochondrial calcium uptake and binding. Ethanol profoundly affects myocardial lipid metabolism. Acetaldehyde diminishes myocardial protein synthesis and inhibits Ca++-activated myofibrillar ATPase. In myocardial failure, a series of possibilities may be responsible for the loss of contractility. Excitation-contraction coupling could be disturbed at the level of the sarcolemma, at the sarcoplasmic reticulum, at the mitochondria, and between calcium and the regulatory proteins. Deficiencies in Ca++ delivery systems of excitation-contraction coupling on the myosin ATPase activity could be responsible for the dimunition in cardiac contractility. Mitochondrial function may also be involved, since mitochondria from failing human hearts are defective with respect to respiratory control and calcium accumulation. Under certain conditions, the relationship of mitochondria to calcium sequestration is very important in influencing contractility. The involvement of contractile and regulatory proteins in myocardial failure cannot be excluded.
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PMID:Cardiac metabolsim: its contributions to alcoholic heart disease and myocardial failure. 15 68

The effects of gram-negative endotoxin (Escherichia coli 4 mg/kg) induced myocardial failure in the pentobarbital-anesthesized dog were examined by monitoring its influence on coronary and systemic hemodynamics and correlating these results with myofibrillar ATPase activity. An identical series of studies was performed incorporating a femoral-femoral arterial-venous shunt to augment venous return. Over a five-hour period, gram-negative endotoxemia was associated with a progressive fall in arterial pressure, stroke volume, cardiac output, coronary flow, and a rise in total peripheral resistance and diastolic coronary vascular resistance. Augmenting venous return by 313 +/- 71 ml/min significantly increased cardiac output, stroke volume, and coronary flow and substantially reduced total peripheral resistance and coronary vascular resistance. Myofibrillar ATPase activity from both endocardium and epicardium was significantly depressed in the endotoxin-shocked preparations. However, with the augmentation of venous return with the A-V shunt in the endotoxin-treated animal, myofibrillar ATPase activity is normal. It appears that endotoxin causes a decrease both in venous return and in cardiac contractility by increasing total peripheral resistance, coronary vascular resistance, and impedance to left ventricular ejection. Augmenting venous return by optimizing preload and reducing afterload prevents any significant increase in total peripheral resistance, coronary vascular resistance, or impedance to left ventricular ejection. This is manifested by a rise in cardiac output, stroke volume, and coronary flow and the preservation of myocardial function. This is the first successful application of left ventricular afterload reduction in noncardiogenic shock.
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PMID:Augmented venous return: protection of the ischemic myocardium during endotoxemia. 16 74


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