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 authors investigated dynamic changes and the interaction of the plasma renin activity (PRA), plasma aldosterone (PAC), i.e. the main representatives of sodium retaining systems, and of the atrial natriuretic factor (ANF) the decisive natriuretic substance in acute expansion of the extracellular volume (ECV) by infusion of two litres of saline in six controls, seven patients with essential hypertension and liver cirrhosis without ascites (6 patients) and with ascites (6 patients). The expansion evoked controversial changes of these systems. It led to a rise of ANF and suppression of PAC and PRA. Although ANF rose after infusion to the roughly similar range (12.4 to 15.7 pmol/l), the natriuretic response to expansion differed significantly in different groups of patients. It was most marked in hypertonic subjects (517.2 to 93.2 mumols/min) and practically zero in ascitic liver cirrhosis (54.2 +/- 44.2 mumols/min). The explanation of this finding may be the persistence of high activity of the renin-angiotensin-aldosterone system despite its partial inhibition by infusion of saline in cirrhosis of the liver (PRA 1.69 +/- 0.66 nmols/l/hr., PAC 1.12 nmol/l). For the renal response to acute expansion of the ECV thus not only the absolute plasma concentration of ANF is decisive but also its ratio to the activity of the sodium retaining renin-angiotensin-aldosterone system.
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PMID:[Mutual interaction of the renin-angiotensin system and the atrial natriuretic factor in the renal response to acute volume loading]. 214 4

The simultaneous measurement of plasma and ascitic fluid N-terminal and C-terminal portions of the 126 amino acid atrial natriuretic factor (ANF) prohormone (proANF) concentrations in six cirrhotic patients revealed that the C-terminus (amino acids 99 to 126; ANF) and the N-terminus (amino acids 1 to 98) are present in high concentrations (mean = 30 +/- 2 fmol/mL and 701 +/- 43 fmol/mL, respectively) in the ascitic fluid of these patients. In addition to the whole N-terminus, the midportion of the N-terminus (amino acids 31 to 67; proANF 31 to 67) was present in ascitic fluid as a separate identity at a concentration of 711 +/- 63 fmol/mL. The concentrations of the C-terminus, proANF 31 to 67, and N-terminus in ascitic fluid were nearly equal to their concentrations in plasma (32 +/- 4 fmol/mL, 761 +/- 54 fmol/mL, and 772 +/- 54 fmol/mL, respectively). The plasma levels of the N-terminus and C-terminus in the cirrhotic patients were considerably higher than the mean plasma concentrations of these peptides in 54 persons without cirrhosis (531 +/- 25 fmol/mL, 371 +/- 22 fmol/mL, and 22 +/- 1 fmol/mL, respectively [p less than 0.05; analysis of variance (ANO-VA)]. Data demonstrate that the whole N-terminus, midportion of the N-terminus (proANF 31 to 67), and C-terminus of proANF are present in ascitic fluid in high concentrations that are nearly equal to plasma levels. This suggests that their presence in ascitic fluid is due to capillary leakage of peptides in the hepatic sinusoids.
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PMID:Presence of the N-terminal and C-terminal portions of the prohormone of atrial natriuretic factor in the ascitic fluid of cirrhotic patients. 215 Apr 13

Thirty-seven patients with volume-retaining disorders (liver cirrhosis with ascites, n = 8; heart failure NYHA III-IV, n = 12; endstage renal failure, n = 17) and twelve healthy age-matched controls were given a small dose (33 micrograms) of hANF (human atrial natriuretic factor). We tested the resulting hemodynamic and renal effects as well as the effect on plasma cyclic GMP levels and compared them with the properties of platelet ANF receptors. The ANF injection evoked an increase in cyclic GMP plasma levels of 19.3 +/- 2.2 nM in healthy controls. This increase tended to be smaller in the cirrhosis group (15.5 +/- 3.3 nM) and in the heart failure group (16.8 +/- 2.3 nM) than in the dialysis group (20.5 +/- 2.5 nM). The invasion rates of cyclic GMP were comparable in all groups, but the evasion rates increased more in the heart failure and endstage renal failure groups (27.9 +/- 7.7 min and 26.1 +/- 3.4 min, respectively) than in the cirrhosis and control groups (14.9 +/- 1.9 min and 14.2 +/- 1.9 min, respectively). Patients with endstage renal failure and congestive heart failure showed a smaller decrease in diastolic blood pressure than controls and patients with liver cirrhosis. Renal actions of ANF were diminished in cirrhosis and heart failure patients. Binding capacities of platelet ANF receptors were higher in the control group (12.2 +/- 1.5 receptors/cell) than in the patient groups (cirrhosis, 7.8 +/- 1.2; endstage renal failure, 8.0 +/- 0.9; heart insufficiency, 8.0 +/- 1.0 receptors/cell), with no differences among the patient groups. Binding affinities were not significantly different. Correlation analysis showed that the relationship between the actions of ANF and the increases in plasma cyclic GMP levels is loose and cannot predict the hemodynamic or renal effects of exogenous ANF in a given patient. Although the behavior of plasma cyclic GMP levels fails to predict the responsiveness of the body to ANF in a given patient, it does reflect the differences between the patient groups and the control group. In contrast, we found no correlation between the properties of platelet ANF receptors and ANF action.
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PMID:Effects of a small bolus dose of ANF in healthy volunteers and in patients with volume retaining disorders. 216 5

We determined human and canine plasma clearance of atrial natriuretic factor (ANF) by lung, liver, and kidney from arteriovenous differences in plasma ANF and measured organ plasma flow. Human subjects had lower plasma ANF concentrations in the pulmonary vein or the pulmonary capillary wedge position when compared with the pulmonary artery, and both sites yielded pulmonary ANF extraction ratios of 24%. Canine lung ANF extraction was 19 +/- 3% and pulmonary ANF clearance was 328 +/- 78 ml/min per m2 vs. 357 +/- 53 ml/min per m2 in man. Hepatic plasma ANF clearance was 216 +/- 26 ml/min with an extraction ratio of 30 +/- 3% in humans and 199 +/- 89 ml/min and 36 +/- 6% in the dog. Renal plasma ANF clearance in human subjects was 78 +/- 12 ml/min per kidney and correlated well with each kidney's creatinine clearance (r = 0.58, P less than 0.05). The mean renal ANF extraction ratio was 35 +/- 4% in human subjects and 42 +/- 6% in the dog. These data quantitate the specific organ ANF clearances by lung, liver, and kidney in human subjects and in dogs and provide a rationale for elevated plasma ANF levels in cirrhosis, renal failure, and diseases accompanied by reduced perfusion of these organs. These findings support the conclusion that plasma ANF concentrations are dependent upon both the stimuli for ANF secretion as well as the specific organ clearances of ANF.
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PMID:Clearance of atrial natriuretic factor by lung, liver, and kidney in human subjects and the dog. 252 90

The role of the atrial natriuretic factor and of the main counteracting sodium-retaining principle, the renin-aldosterone system, in acute volume regulation of cirrhosis of the liver has been investigated. Central volume stimulation was achieved in 21 patients with cirrhosis, 11 without and 10 with ascites, and 25 healthy controls by 1-hr head-out water immersion. Immersion prompted a highly significant (p less than 0.001) increase of atrial natriuretic factor plasma concentrations in cirrhotic patients without ascites from 8.5 +/- 1.3 fmoles per ml to 16.5 +/- 2.6 fmoles per ml, comparable to the stimulation in control subjects (6.0 +/- 0.6 fmoles per ml to 13.6 +/- 2.6 fmoles per ml). In cirrhotic patients with ascites, atrial natriuretic factor increase (from 7.7 +/- 1.3 fmoles per ml to 11.4 +/- 2.3 fmoles per ml) was blunted (p less than 0.05). Plasma renin activity and plasma aldosterone concentration were elevated in cirrhotic patients, especially in the presence of ascites. Following immersion, plasma renin activity and plasma aldosterone concentration were reduced similarly in all groups. Water immersion induced a more pronounced natriuresis and diuresis in control subjects than in cirrhotic patients. Neither atrial natriuretic factor nor plasma renin activity nor plasma aldosterone concentration alone correlated to sodium excretion. However, atrial natriuretic factor to plasma aldosterone concentration ratios were closely correlated to basal and stimulated natriuresis in cirrhotic patients, particularly in those with ascites. These data suggest that atrial natriuretic factor and the renin-aldosterone system influence volume regulation in patients with cirrhosis.
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PMID:Atrial natriuretic factor and renin-aldosterone in volume regulation of patients with cirrhosis. 252 81

Atrial natriuretic factor (ANF) is a humoral agent isolated in recent years from cardiac atrial tissue, and produced by atrial cardiocytes as a peptide precursor containing 152 amino acids. In secretory atrial granules, it is stored in reserve form as a prohormone and released into circulation as a 28-amino acid peptide from the C-terminal portion of the peptide precursor representing the active circulating hormone. ANF possesses potent natriuretic, myorelaxant, vasodilatory and blood pressure-lowering properties. Besides, it inhibits renin, aldosterone and vasopressin secretion. It is present also in the CNS and its function is closely related to the sympathetics nerves. By its direct renal and vascular effect, renin-angiotensin-aldosterone system and vasopressin inhibition and, by its neuromodulatory action on the central and sympathetic nerves, ANF plays an important role in electrolyte, volume and pressure homeostasis. The development of a radioimmunoassay for ANF determination in the plasma of rats and man enabled us to follow up its changes under various experimental conditions (water deprivation, increased or decreased salt intake, effect of anaesthetics, ontogenetic changes in ANF concentration during development of hypertension in the spontaneously hypertensive rat) and in clinical studies (effect of ECV expansion in controls, arterial hypertension, liver cirrhosis as well as ANF changes in congestive heart failure or chronic renal failure). These findings of ours have supported the concept that ANF represents an important adaptive and corrective mechanism mobilized during intravascular volume and blood pressure changes in an effort to normalize these. ANF is expected to find use also in the treatment of oedema, arterial hypertension and acute renal failure.
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PMID:Atrial natriuretic factor and its role in the regulation of electrolyte, volume and pressure homeostasis. 252 70

The responsiveness of atrial natriuretic factor (ANF) to central volume expansion and its role as a determinant of the natriuretic and diuretic responses of cirrhotic patients was evaluated utilizing water immersion (WI). Following equilibration on a 10-mEq sodium diet, 9 seated cirrhotic patients were studied during 3 h of WI. Before WI, plasma ANF levels (10.9 +/- 2.4 fmol/ml) were similar to those previously observed in normal sodium-replete subjects (7.7 +/- 0.9 fmol/ml). Five of the 9 cirrhotic subjects manifested an exaggerated peak ANF response, whereas the remaining 4 manifested increases similar to those of normals. The concomitant natriuretic response varied widely, ranging from absent to markedly exaggerated responses. The peak urinary sodium excretion varied independently of peak plasma levels of ANF and peak change of ANF from the prestudy hour (r = 0.36, p greater than 0.20, and r = 0.46, p greater than 0.20, respectively). Thus, in contrast to normal subjects, in whom the immersion-induced natriuresis correlated closely with the changes in ANF, the natriuretic responses of cirrhotic patients were dissociated from the concomitant increases in ANF. These observations indicate that sodium retention in cirrhosis is not attributable to impaired ANF release.
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PMID:Relationship between plasma ANF responsiveness and renal sodium handling in cirrhotic humans. 252 78

We compared the natriuretic response to a standard dose of atrial natriuretic factor in nine patients with early cirrhosis (no ascites or edema) with the response in normal subjects displaying a range of baseline sodium excretions due to different sodium intakes (20 mmoles per day, n = 9; 100 mmoles per day, n = 9, and 200 mmoles per day, n = 9). In these normal subjects, sodium output rose, in the same order, from 49 +/- 12 to 177 +/- 26, from 116 +/- 21 to 365 +/- 106 and from 228 +/- 29 to 901 +/- 85 mumoles per min in the first 20 min after 100 micrograms atrial natriuretic factor (human atrial natriuretic factor 99-126). Thus, irrespective of basal excretion, natriuresis rose by at least 2-fold. In the cirrhotic patients, natriuresis rose from 173 +/- 42 to 305 +/- 77 mumoles per min, that is by hardly 1-fold, significantly less than in the normal subjects (p less than 0.01). Renal function studies indicated that atrial natriuretic factor caused less rise in glomerular filtration rate and in fractional sodium excretion. Atrial natriuretic factor induced a fall in blood pressure only in the cirrhotic group, from 130 +/- 4/81 +/- 2 to 108 +/- 4/68 +/- 3 mmHg (p less than 0.001). Plasma atrial natriuretic factor was not low in the cirrhotic patients. Although these data are compatible with a primary disturbance of sodium excretion in early cirrhosis without ascites, such an explanation is complicated by the concomitant drop in blood pressure after atrial natriuretic factor.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Blunted natriuretic response and low blood pressure after atrial natriuretic factor in early cirrhosis. 213 31

The simultaneous measurement of plasma and ascitic fluid atrial natriuretic factor (ANF) concentrations in six cirrhotic patients revealed that ANF is present in high concentrations (mean = 89 +/- 4 pg/ml) in the ascitic fluid of these patients. The concentration of atrial natriuretic factor in ascitic fluid was nearly equal to the concentration in plasma (96 +/- 8 pg/ml). The plasma levels of ANF in the cirrhotic patients were considerably higher than the mean plasma concentration of this peptide hormone in 54 persons without cirrhosis (67 +/- 3 pg/ml). The data demonstrate that atrial natriuretic factor is present in ascitic fluid in high concentrations that are nearly equal to that in plasma. This suggests that its presence in ascitic fluid is due to capillary leakage in the hepatic sinusoids.
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PMID:Atrial natriuretic factor in the ascitic fluid of cirrhotic patients. 253 Feb 96

Plasma immunoreactive atrial natriuretic factor (irANF) levels and the effects of alpha-human ANF (alpha-hANF) infusion were investigated in 7 patients with liver cirrhosis and ascites. Under basal conditions, supine blood pressure (BP) averaged 136/76 +/- 9/4 mm Hg (mean +/- SEM). Plasma irANF concentrations (124 +/- 33 pg/ml) were higher (p less than 0.01) than those in age-matched normal subjects (47 +/- 5 pg/ml). Plasma renin activity (PRA 5.9 +/- 2.2 ng/ml/h), aldosterone (18 +/- 7 ng/dl) and norepinephrine (NE, 66 +/- 5 ng/dl) levels were also elevated compared to the age-related normal range. Alpha-hANF infusion for 60 min at 0.036 micrograms/kg/min decreased the mean BP (-14%; p less than 0.05), increased PRA (+179%; p less than 0.05) and plasma NE (+24%; p less than 0.05). Glomerular filtration rate (GFR), effective renal plasma flow (ERPF), diuresis and natriuresis were not modified. A subsequent 60-min infusion of alpha-hANF at 0.067 micrograms/kg/min produced a marked fall in mean BP (-26%; p less than 0.001), hemoconcentration (hematocrit +6%; p less than 0.001) despite stable body fluid balance and a further increase in PRA (+350%, p less than 0.005). GFR and ERPF were severely reduced (-55 and -56%, respectively; p less than 0.001), while diuresis and natriuresis were not modified. Plasma aldosterone was unaltered during, but rose (+72%; p less than 0.01) after the cessation of alpha-hANF infusion. Variations in natriuresis during alpha-hANF infusion correlated positively with BP (r = 0.47; p less than 0.01), ERPF (r = 0.53; p less than 0.01) or GFR (r = 0.51; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hypotension and renal impairment during infusion of atrial natriuretic factor in liver cirrhosis with ascites. 253 Sep 3


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