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)

For intracranial diseases, plasma atrial natriuretic peptide (ANP), antidiuretic hormone (ADH) and aldosterone were determined and their effects on the development of hyponatremia with central origin were studied. The subjects were 71 cases of intracranial diseases which were admitted to our hospital during a period of 1 year from March, 1989 to March, 1990. The diseases were broken down to subarachnoid hemorrhage 26 cases, hypertensive intracerebral hemorrhage 19 cases, head injury 12 cases, cerebral infarction 11 cases and 3 other cases. Serum-urine electrolytes, plasma ANP and ADH were determined in the acute stage on Day 1 to 4, in the hyponatremia stage on Day 5 to 14 and in the chronic stage on Day 15 downward. Hyponatremia was defined as the serum sodium level of 130 mEq/l or less. Cases evidently having other causes such as heart failure and renal insufficiency were excluded. In the normal control group of persons who were admitted to our hospital for a close checkup (n = 20), plasma ANP was 26.5 +/- 11.6 pg/ml (10-50); levels of 50 pg/ml or more were regarded as abnormally high. 1) Hyponatremia was found in 18 cases (25.4%), subarachnoid hemorrhage in 7 cases, hypertensive intracerebral hemorrhage in 4 cases, head injury in 5 cases and others in 2 cases. 2) The time of onset of hyponatremia was on the 8.3 hospital day. The duration was 7.2 days. The minimum serum sodium level was 124.6 mEq/l. 3) There was no significant change in the plasma aldosterone level at each stage.2+ Predicting development of hyponatremia from plasma ADH and ANP levels in the acute stage is difficult. Inadequate secretion of ANP rather than ADH appeared to be an important factor for the development of hyponatremia, but the plasma ANP level was not always abnormally high, so involvement of other sodium diuretic factors should also be kept in mind.
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PMID:[A study of plasma atrial natriuretic peptide, antidiuretic hormone and aldosterone levels in a series of patients with intracranial disease and hyponatremia]. 153 80

All hyponatremic states have in common elevation of vasopressin. Without this the loss of salt would be followed by appropriate diuresis and normonatremia. If hyponatremia is triggered by a volume change as in heart failure or portal cirrhosis not only is ADH released but the mechanisms that control salt retention create an essentially sodium free urine, always less than 20 mEq/L. If the initial event is inappropriate ADH secretion whether it be cerebral disease, neoplasm, a pulmonary lesion or a growing list of drugs; there is no related signal for salt retention and urine sodium and tonicity are high, the latter usually higher than that of plasma. If salt loss is due to intrinsic renal disease, diuretics, osmotic or otherwise, or adrenal failure urinary sodium is variable depending upon the magnitude of the response to volume of salt retaining factors. Because hyponatremia is often present with major illness and because more than one factor may be involved in its genesis, the establishment of its origin and appropriate treatment remain a diagnostic and therapeutic challenge.
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PMID:Hyponatremia: manifestations and treatment. 162 51

Experimental myocardial infarction is a model of cardiac overload due to amputation of part of the cardiac muscle. The development of cardiac failure depends on the size of the infarct and the time factor. This model of overload is associated with changes of the phenotype of the remaining healthy muscle and with peripheral vascular modifications partially dependent of the activation of pressor and/or deactivation of dilator systems. These changes are proportional to the size of the infarction at a given time after induction of the model. The degree of right ventricular hypertrophy and the decrease in blood pressure reflect the severity of infarction and the deterioration of the remaining myocardial function, affecting the haemodynamics both before and after the left ventricle. The increases in the 1/3 forms of isomyosins, the amount of subendocardial collagen, the biosynthesis, stocking and secretion of ANF are related to the infarct size and degree of overload. Similarly, the concentration of cyclic GMP is proportional to the infarct size. These parameters reflect ventricular overload, the increase of stress and energy deprivation of the remaining healthy muscle. The activation of peripheral pressor systems is also dependent on the infarct size reflects the effect of cardiac pump dysfunction on the kidney, liver, brain and endothelium. Large infarcts are associated with increased circulating renin and renal concentrations, with a decrease in angiotensinogen levels related to its consumption by the renin and to reduced hepatic synthesis and also with increased secretion and biosynthesis of vasopressin by the hypothalamus. In this model, Perindopril is beneficial by decreasing the cardiac load. It reduces the blood pressure, causes regression of bi-auricular and right ventricular hypertrophy. Changes in myosin isoenzyme configuration regress and subendocardial fibrosis and ANF concentrations are normalised. The effects of ACE inhibitors in this context, though very beneficial, are limited by the impossibility of normalising cardiac load and stress when the initial amputation of cardiac contractile mass exceeds 40%.
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PMID:[Experimental myocardial infarction in the rat. Effect of perindopril]. 166 27

Circulating plasma concentrations of norepinephrine, renin, angiotensin and vasopressin are increased in congestive heart failure. By increasing ventricular afterload, heart failure is further worsened, which in turn--in a vicious cycle--stimulates neurohumoral vasoconstrictor mechanisms. Furthermore, because of the compensatory but excessive stimulation of the sympathomimetic system, a down-regulation and desensitization particularly of the myocardial beta 1 receptors and depletion of myocardial catecholamine occurs in chronic heart failure. These defects may be restored toward normal by interventions that attenuate the activity of the sympathetic nervous system. A direct approach to modify the excessive vasoconstriction is to administer systemic vasodilator drugs, but despite favorable short-term effects, tolerance developed to most of these drugs during long-term treatment. One reason for the loss of effectiveness is the reflex activation of the sympathetic system, which increases vasoconstrictor hormone concentrations. Activation of the renin-angiotensin system can be modified effectively by angiotensin-converting enzyme inhibitors that have shown favorable responses in patients with chronic heart failure. Beta-blocking agents interfere with endogenous sympathetic activation and have produced beneficial effects in patients with congestive cardiomyopathy. Long-term treatment is associated with up-regulation of the number of beta receptors and an improved responsiveness to catecholamines. Owing to the negative inotropic effects of beta-blocking agents, some of the patients with severe heart failure deteriorated hemodynamically and clinically. Theoretically, it should be advantageous to have a substance that combines protection against excessive beta stimulation with a mild inotropic support to prevent cardiac decompensation. This may be achieved by a selective beta 1-partial agonist like xamoterol.
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PMID:Interrupting the adaptive changes in congestive heart failure. 167 86

It has been hypothesized that a decreased activity of vagal afferents might contribute to the activation of neurohumoral systems in congestive heart failure. Therefore, we studied the effects of vagal nerve blockade by local anesthesia on neurohormones in six conscious dogs before and after induction of heart failure by rapid right ventricular pacing (250 beats/min, 10 days). In healthy dogs, vagal blockade significantly increased plasma vasopressin levels (from 1.5 +/- .6 to 13.7 +/- 10.5 pg/ml, p less than 0.02), without significantly affecting plasma catecholamines and renin. After 10 days of pacing, mean arterial pressure and cardiac output were decreased, right atrial and pulmonary arterial pressures and plasma levels of norepinephrine, dopamine, and atrial natriuretic peptide were increased. In this state, vagal blockade significantly increased plasma renin activity (from 1.52 +/- .43 to 3.18 +/- .54 ngAI/ml/h, p less than 0.02) and plasma vasopressin (from 4.2 +/- 3.3 to 89.1 +/- 54.9 pg/ml, p less than 0.02), this increase being significantly higher than in healthy dogs. We conclude that in these dogs with low cardiac output state, which resembles early heart failure, vagal afferent activity is increased and effectively suppresses renin and vasopressin. This does not exclude the possibility that in later stages of heart failure vagal afferent dysfunction may develop, resulting in neurohumoral disinhibition.
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PMID:Effects of vagal blockade on neurohumoral systems in conscious dogs with heart failure. 169 88

Seventy four patients aged 35-74 years who had mitral valvular disease were examined for renin, angiotensin II, aldosterone, and vasopressin, of whom 49 patients were diagnosed as having a mitral valve defect with prevalent stenosis, 25 presented with a mitral valve defect with prevalent heart failure. Circulatory disorders, Stages I-II, were found in 41 patients, Stage IIB in 23, and Stage III in 10 patients. There were no significant differences in the parameters of the renin-angiotensin-aldosterone system (RAAS) and vasopressin in untreated adult and elderly patients with mitral valvular disease at rest. As circulatory disorders progressed, the RAAS parameters significantly increased in all the groups. However, the patients with prevalent stenosis showed higher blood renin levels than did those with prevalent heart failure, irrespective of its severity. In refractory heart failure, the significant differences remained to a greater extent only for renin. The treatment with peripheral vasodilators (isosorbide dinitrate and corinfar) resulted in compensatory activation of the neurohumoral vasoconstrictive system, thereafter the RAAS parameters significantly increased after the drugs.
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PMID:[Renin-angiotensin-aldosterone system and vasopressin in adult and aged patients with acquired mitral valve defects]. 179 80

The systemic and regional hemodynamic effects of arginine vasopressin receptor antagonism (AVPA) and angiotensin-converting enzyme inhibition (ACEi) were examined in rabbits with acute left ventricular failure induced by repetitive direct current (DC) shock. Hemodynamic measurements in 24 rabbits 24 h after DC shock compared with 6 sham-operated controls demonstrated a lowered cardiac output (602 +/- 26 vs. 920 +/- 35 ml/min, P less than 0.01), increased left ventricular end-diastolic pressure (LVEDP, 13.6 +/- 1.3 vs. 1.9 +/- 0.5 mmHg, P less than 0.01) and a raised peripheral resistance (9,734 +/- 495 vs. 6,479 +/- 305 dyn.s.cm-5, P less than 0.01). Cerebral blood flow was not altered in rabbits with acute left ventricular failure but intestinal (29 +/- 2 vs. 53 +/- 9 ml/min, P less than 0.01) and renal (82 +/- 6 vs. 130 +/- 8 ml/min, P less than 0.01) blood flows were significantly reduced. No hemodynamic changes were observed after AVPA alone in the acute heart failure group and ACEi alone reduced LVEDP and increased renal vascular conductance. Treatment with both drugs (i.e., AVPA + ACEi) resulted in a significant increase in cardiac output (21%) and a decrease in blood pressure (19%) and peripheral resistance (34%) and restored renal and intestinal blood flows to near normal levels. Thus both vasopressin and angiotensin contribute to the overall increase in peripheral resistance in this model and to the decrease in intestinal and renal blood flow observed. Presumably blockade of one system produced little hemodynamic change because of compensatory increases in the other system.
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PMID:Systemic and regional effects of vasopressin and angiotensin in acute left ventricular failure. 182 56

Previous studies from our department revealed that congestive heart failure (CHF) is paralleled by a decrease in number of sarcolemmal beta-receptors due to excessive levels of circulating endogenous catecholamines. In contrast, the myocardial H2-receptor system proved to be not affected (Am. Heart J. 101; 569, 1981). The first clinically tested specific H2-receptor agonist impromidine (IMP) turned out to be a potent stimulator in patients with CHF which were insensitive to catecholamine stimulation (Pharmacol. Ther. 24; 165, 1984). Though the overall results of such an H2-receptor stimulation were salutary with favourable hemodynamic effects, the narrow therapeutic range, high costs of synthesis and the arrhythmogenic potential of IMP limited its broad clinical application in large scale trials. - Recently developed phenylpyridylalkylguanidines (J. Med. Chem. 32, 1963, 1989) were investigated under in vitro and in vivo conditions in the guinea-pig under physiologic and pathophysiologic conditions using IMP as reference. - Compounds tested were arpromidine (INN) (BU-E-50) and the difluorinated analogues BU-E-75 and BU-E-76, all guanidine-type H2-agonists with additional H1-antagonistic properties due to a pheniramine like moiety. In the isolated perfused heart all three new compounds were more potent in increasing cardiac contractile force and coronary flow but less effective on heart rate and less arrhythmogenic. The same could be established under in vivo conditions where BU-E-76 was more potent than BU-E-75, arpromidine and IMP, respectively, in augmenting LVdp/dt, LVP, cardiac output and systemic blood pressure, but all compounds revealed to have less chronotropic and arrhythmogenic potentials. In the vasopressin-induced acute heart failure model BU-E-76 and BU-E-75 normalized all contractile parameters in contrast to arpromidine and IMP. Within minutes it is concluded that the new H2-receptor agonists may represent a promising therapeutic improvement for treatment of CHF patients with a cardiovascular profile superior to IMP and conventional catecholamines.
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PMID:Therapeutic value of H2-receptor stimulation in congestive heart failure. Hemodynamic effects of BU-E-76, BU-E-75 and arpromidine (BU-E-50) in comparison to impromidine. 182 32

The purpose of the present study was to measure plasma levels of atrial natriuretic peptide (ANP) in patients with acute myocardial infarction without heart failure, and also to assess the temporal sequence of changes of plasma ANP during the first hours of recovery from myocardial infarction. The study was performed in 22 patients who were admitted to the Intensive Care Unit with the diagnosis of acute myocardial ischaemia that had an evolution of less than 6 h. Blood samples were drawn on admission and at 1, 8, and 24 h, and plasma concentrations of ANP, renin, aldosterone, epinephrine, norepinephrine and vasopressin were measured. Compared with control subjects, on admission patients showed increased plasma levels of ANP, as well as increased plasma renin activity (PRA), aldosterone, norepinephrine, epinephrine, dopamine, and antidiuretic hormone (ADH). ANP, but not renin or aldosterone plasma values, decreased with time, and there was a significant correlation between ANP and time after onset of pain. No increase in plasma creatinine was observed during the hospital stay, and the patients showed a negative fluid balance. No relationship was found between the location or extension of the infarction, or morphine treatment and ANP plasma levels. The high levels of ANP seem to counteract the haemodynamic and fluid-retention effects of the vasoconstrictive factors released after myocardial infarction.
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PMID:Atrial natriuretic peptide in patients with acute myocardial infarction without functional heart failure. 182 81

In 1984 we demonstrated in an animal model of chronic congestive heart failure due to rapid right ventricular pacing in chronically instrumented dogs, that the inhibition of the renin-angiotensin-aldosterone system by captopril from the onset of pacing has beneficial effects on hemodynamic and neurohumoral mechanisms. In contrast to control animals, dogs on a chronic therapy with the ACE-inhibitor showed no significant increase in peripheral vascular resistance, a reduced decline of cardiac output and no significant increase of mean pulmonary arterial pressure. Chronic ACE-inhibition led to a significant reduction of the secretion of aldosterone, to an attenuation of the activation of the sympathetic activity and to a prevention of inappropriate stimulation of vasopressin secretion. This was associated with a reduction in symptoms and a lack of fluid retention, whereas control animals developed pleural infusions and ascites. Similar beneficial effects have been demonstrated in rats following myocardial infarction during a long-term therapy with captopril on hemodynamic parameters, heart size, and survival. Thus, early inhibition of the renin-angiotensin-aldosterone system in heart failure may be an attractive approach for treatment in patients with ventricular dysfunction even before symptoms develop.
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PMID:[ACE inhibition: mechanisms of cardioprotection in chronic experimental heart failure]. 183 Sep 9


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