Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of encainide administration on steady-state plasma digoxin levels was evaluated in 17 patients receiving stable doses of digoxin. A paired t test, comparing plasma digoxin levels (mean +/- standard error) before encainide therapy (1.05 +/- 0.14 ng/ml) and after 2 weeks of encainide, 100 mg/day (1.03 +/- 0.11 ng/ml) or 200 mg/day (1.2 +/- 0.2 ng/ml), indicates no significant (p greater than 0.05) change in digoxin levels. These results were confirmed in a second study of 10 patients with severe congestive heart failure. Also, no difference in efficacy of either drug was observed and changes in dosing of digoxin were not required. Plasma concentrations of encainide and its 2 major metabolites, O-demethyl encainide (ODE) and 3-methoxy-O-demethyl encainide, significantly increased by 31.6%, 43.1% and 35.6% after concomitant cimetidine administration in 13 healthy adult men receiving 75 mg/day of encainide. However, a retrospective evaluation of 33 patients receiving both drugs did not reveal any clinically significant interactions. Retrospective evaluation of patients enrolled in clinical studies who received concomitant digoxin (268), antiarrhythmics (118), anticoagulants (78), antidiabetics (40), antipsychotics (23), beta blockers (88), calcium-channel blockers (24) or diuretics (229) did not reveal any clinically significant interactions with encainide. Similarly, in vitro protein binding studies did not reveal any clinically significant interactions with encainide or its major metabolites. Six patients with moderate to severe renal impairment (creatinine clearance 10 to 38 ml/min) received 25 mg of encainide, 3 times/day, for 7 doses. Plasma encainide, ODE and 3-methoxy-O-demethyl concentrations were similar to those observed in normal subjects who had received twice the dose of encainide, and steady-state apparent oral clearance of encainide was reduced by 66% with renal impairment. Based on these data it is recommended that in patients with moderate to severe renal impairment encainide be initiated at one-third the normal dose, or 25 mg once a day. Doses may be elevated in small increments at 1-week intervals if needed for efficacy. The effect of hepatic impairment on the pharmacokinetics of encainide was studied in 7 patients with clinically documented cirrhosis. Compared with normal subjects studied using a similar protocol, the plasma concentrations of encainide were elevated significantly due to a 6-fold decrease in oral clearance. However, since plasma concentrations of the active metabolite ODE were correspondingly lower, specific encainide dosing instructions for patients with hepatic impairment are not indicated.
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PMID:Drug interaction studies and encainide use in renal and hepatic impairment. 287 43

The pharmacokinetics of ibopamine was studied after single dose and after single and multiple dosing. The studies after single dose were conducted in normal subjects (NS) and in patients with congestive heart failure (CHF) of NYHA functional classes II, III and IV, in patients with chronic renal impairment (CRI), with hepatic cirrhosis (HC) and in elderly patients. Furthermore, ibopamine-quinidine pharmacokinetic interaction and the effects of food on plasma kinetics were evaluated in NS. The studies after single and multiple dosing were conducted in CHF patients. The effects were also studied of chronic oral ibopamine treatment on the pharmacokinetics of digoxin after chronic oral dosing and of treatment with digoxin on ibopamine pharmacokinetics. Ibopamine appears to be rapidly and extensively absorbed, quickly hydrolyzed to epinine and then excreted mainly through the kidneys either after being sulpho-conjugated or oxidized to homovanillic acid and 3,4-dihydroxyphenylacetic acid. Epinine is thought to be the therapeutically active moiety of the drug. In patients with CHF epinine pharmacokinetics does not depend on the NYHA functional class, and it falls within the same area as that in NS; the pharmacokinetics of epinine does not vary during the repeated administration of the drug for one month. In patients with CHF the pharmacokinetic data do not suggest the need to adjust the dose according to the NYHA functional class. In patients with CRI the pharmacokinetics of epinine does not vary with the degree of renal impairment. In HC patients AUC and Cmax of epinine seem to be higher than in NS; in these patients a higher amount of epinine is excreted into urine.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Clinical pharmacokinetics of ibopamine on different diseases and conditions. 290 70

The diuretic effect of the supine position was evaluated in six patients with cirrhosis and ascites and six with congestive cardiac failure. All patients received 1 mg bumethanide intravenously and were randomly assigned to either bed rest in the supine position or normal daily activity in the upright position for the next six hours. The diuretic response was similar in patients with heart failure and cirrhosis, and was significantly greater in the supine than in the upright position: mean 1,133 v 626 ml/6 h (p less than 0.01). The natriuresis was similarly greater during recumbency: mean sodium 96 v 45 mmol (mEq)/6 h (p less than 0.01), and the excreted potassium in six hours was similar in both postures. The glomerular filtration rate was 100 and 66 ml/min (p less than 0.01) and the heart rate 76 and 83 beats/min (p less than 0.05) in the supine and upright positions, respectively. Plasma concentrations of noradrenaline, renin, and aldosterone rose significantly during the upright position. The results suggest that the attenuated response to intravenous bumethanide in the upright position and during normal daily activity may be due to the activation of several, homoeostatic mechanisms which may reduce the excretion of water and salt.
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PMID:[Effect of posture on the diuretic treatment of decompensated cirrhosis and heart failure]. 291 77

Atrial natriuretic factor (ANF), a recently sequenced cardiac peptide, has been shown to have potent natriuretic, diuretic, and vasodilating effects in several species. We have developed a radioimmunoassay to measure the levels of immunoreactive ANF in human plasma. Plasma levels of ANF in healthy volunteers on a low sodium diet were 9.8 +/- 1.4 pmol/liter and increased to 21.9 +/- 3.0 on a high sodium diet. The levels of atrial natriuretic factor correlated directly with urinary sodium and inversely with plasma renin activity and plasma aldosterone levels. Patients with marked edema due to congestive heart failure had plasma levels of atrial natriuretic factor five times higher than normal (P less than 0.05), whereas patients with cirrhosis and edema had levels that were not different from normal. These results suggest that atrial natriuretic factor plays an important role in the adaptation to increased sodium intake.
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PMID:Plasma levels of immunoreactive atrial natriuretic factor in healthy subjects and in patients with edema. 293 71

A sensitive and specific radioimmunoassay for alpha-human atrial natriuretic polypeptide (alpha-hANP) was developed to determine its plasma level. Anti-alpha-hANP rabbit serum was specific for the N-terminus and ring structure of alpha-hANP, and showed no appreciable cross-reactions with other neuropeptides. The lowest level of alpha-hANP detectable by this radioimmunoassay was 4 pg per tube. The intra- and inter-assay coefficients of variation were 4.6-11.4% and 7.9-11.8%, respectively, and the recovery rates at 4 concentrations were 62.6-74.0%. The fasting plasma alpha-hANP concentration in normal subjects were 19.3 +/- 1.0 ng/l (mean +/- SE; n = 54), and there was no sex difference. The plasma alpha-hANP level in normal subjects fell significantly during water deprivation and increased significantly on infusion of hypertonic saline. The mean plasma levels of alpha-hANP were higher than normal in patients with essential hypertension, liver cirrhosis, congestive heart failure and chronic renal failure. Our results indicate that this radioimmunoassay is suitable for determining the alpha-hANP concentration in human plasma and can assess changes in pathological and physiological states.
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PMID:Radioimmunoassay for atrial natriuretic peptide: method and results in normal subjects and patients with various diseases. 294 73

Alpha-human atrial natriuretic polypeptide (alpha-hANP) was applied to 16 clinical patients, 6 patients with essential hypertension, 7 patients with congestive heart failure and 3 patients with cirrhosis. Following intravenous bolus injection of 400 micrograms of synthetic alpha-hANP, a hypotensive effect of very rapid onset was found, which was more potent in the hypertensive patients than in the normotensive cases. Cardiac functions were improved significantly with a similar time course as the depressor response in the cases of heart failure or hypertension. Hemodynamic observations showed a marked increase in cardiac output, cardiac index, stroke volume, ejection fraction and ejection rate, and a concomitant decrease of the pressure in the right side of the heart and pulmonary circulation in these subjects. In addition, the renal response to alpha-hANP induced obvious increases in urine volume, electrolytes and creatinine excretions in all the subjects. Finally, plasma levels of aldosterone, Arg-vasopressin and noradrenaline were also altered by alpha-hANP. No significant side effects were registered. The above result confirms the therapeutic actions of alpha-hANP in human subjects and opens the possibility to research alpha-hANP as a powerful pharmacological tool as well as potential new medicine for human disorders.
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PMID:Therapeutic actions of alpha-human atrial natriuretic polypeptide in 16 clinical cases. 295 43

The discovery of the first well-defined natriuretic hormone, the Atrial Natriuretic Factor (ANF), has prompted research on its impact on volume regulation in health and disease. The natriuretic, diuretic, and smooth muscle-relaxing properties suggest an important role of this novel hormone in pathophysiological states with sodium or volume retention, such as congestive heart failure or cirrhosis of the liver. Investigations on the implications of ANF in liver disease have been performed for little more than 1 year, and results are still controversial in many respects. At present, it seems very likely that there is no absolute deficiency of plasma ANF in patients with cirrhosis. Moreover, elevated plasma levels in cirrhotics with ascites have been reported by several groups. However, as yet, a molecular characterization of this increased immunoreactivity is still lacking. There is disagreement on the reduced release of and renal response to ANF in subgroups of cirrhotics; however, stimulus-response-coupling might be impaired. Further studies are needed to elucidate the pathophysiological implications and therapeutical potential of ANF in patients with chronic liver disease.
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PMID:Atrial natriuretic factor. Possible implications in liver disease. 295 38

The discovery of the first well-defined natriuretic hormone, the Atrial Natriuretic Factor (ANF), has prompted research on its impact on volume regulation in health and disease. The natriuretic, diuretic, and smooth muscle-relaxing properties suggest an important role of this novel hormone in pathophysiological states with sodium or volume retention, such as congestive heart failure or cirrhosis of the liver. Investigations on the implications of ANF in liver disease have been performed for a short period only, and results are still controversial in many respects. At present, it seems very likely that there is no absolute deficiency of plasma ANF in patients with cirrhosis. Moreover, elevated plasma levels in cirrhotics with ascites have been reported by several groups. However, as yet, a molecular characterization of this increased immunoreactivity is still lacking. There is disagreement on the reduced release of and renal response to ANF in subgroups of cirrhotics; however, stimulus-response-coupling might be impaired. Further studies are needed to elucidate the pathophysiological implications and therapeutical potential of ANF in patients with chronic liver disease.
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PMID:[Atrial natriuretic factor. Initial results of possible significance in liver cirrhosis]. 296 83

Using RIAs for the N- and C-terminal fragments of the human atrial natriuretic polypeptide (ANP) precursor gamma ANP, that is gamma ANP-(1-25), and alpha ANP [gamma ANP-(99-126)], we studied the secretion of gamma ANP-derived peptides from the heart in normal subjects and patients with heart disease, chronic renal failure, and cirrhosis. We detected gamma ANP-(1-25)-like immunoreactivity (-LI) in plasma from normal subjects (n = 17) in considerable amounts [mean, 510 +/- 62 (+/- SE) pg/mL (174 +/- 21 pmol/L)]; the mean plasma alpha ANP-LI level at the same time in these subjects was 32.8 +/- 4.4 pg/mL (10.7 +/- 1.4 pmol/L). Gel permeation chromatographic analysis of plasma samples from normal subjects and patients with heart disease and chronic renal failure revealed two major components; one was alpha ANP, and the other was the 10K N-terminal gamma ANP fragment (N-peptide) resulting from the removal of alpha ANP (3K) from gamma ANP (13K). In addition, gamma ANP (13K), which possessed both gamma ANP-(1-25)-LI and alpha ANP-LI, and beta ANP, an antiparallel dimer of alpha ANP, were detected in some patients as minor components. A significant positive correlation between plasma levels of the N-terminal gamma ANP fragment and alpha ANP (P less than 0.01) and almost equal step-ups in the coronary sinus plasma levels of the N-terminal gamma ANP fragment and alpha ANP suggest that they are cosecreted in equimolar amounts. The high molar ratio of plasma gamma ANP-(1-25)-LI to alpha ANP-LI (17.4 +/- 1.4) in normal subjects and the significantly higher ratio in patients with chronic renal failure (36.9 +/- 7.1; P less than 0.01) suggest the slower clearance of the N-terminal gamma ANP fragment than alpha ANP and a role for the kidney in its degradation. Since the molar ratio of plasma gamma ANP-(1-25)-LI to alpha ANP-LI in patients with cirrhosis (20.7 +/- 2.7) was similar to that in normal subjects, it is unlikely that the N-terminal gamma ANP fragment is metabolized by the liver. In patients with heart disease, plasma gamma ANP-(1-25)-LI and alpha ANP-LI levels were higher in those with cardiac decompensation and were positively correlated with right atrial pressure, pulmonary arterial pressure, and pulmonary capillary wedge pressure, indicating cosecretion of the N-terminal gamma ANP fragment and alpha ANP in response to atrial stretch.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Gamma-atrial natriuretic polypeptide (gamma ANP)-derived peptides in human plasma: cosecretion of N-terminal gamma ANP fragment and alpha ANP. 297 Apr 70

An explosion of research over the last seven years has led to the discovery and characterization of a peptide, originating in the heart's atria, that possesses impressive vasorelaxant and natriuretic properties. Although the several atrial peptides that have been isolated by researchers working in different laboratories vary in length, all contain the same core sequence. Cardionatrin I, a 28-amino acid peptide, is the likely active circulating hormone. In the atrial peptide's action on vascular smooth muscle, it appears especially to counter the effects of angiotensin II. The peptide's effects on renal hemodynamics and sodium excretion include a marked increase in glomerular filtration rate. Atrial hormone also induces impressive natriuresis in experimental animals, for which an increase in glomerular filtration rate may be a necessary component. Atrial hormone has been found to reduce arterial blood pressure in both animals and humans. In experimental animals, the peptide appears to lower blood pressure by different mechanisms in high- and low-renin forms of hypertension, and to lower pressure to a greater degree and with lower doses in the former as compared with the latter. In patients with essential hypertension, primary aldosteronism, congestive heart failure, renal failure, and perhaps ascitic cirrhosis, plasma ANH levels tend to be higher than they are in normotensive individuals. Atrial hormone causes marked and sustained suppression of renal renin secretion and, thus, of plasma renin levels. In addition, atrial hormone blocks aldosterone secretion and opposes the vasoconstrictive effects of angiotensin II and the sodium-retaining action of aldosterone.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Atrial natriuretic hormone: a regulator of blood pressure and volume homeostasis. 297 65


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