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)

Atrial natriuretic factor (ANF) is a cardiac hormone with potent natriuretic, diuretic, and vasorelaxant properties. Although abnormalities in ANF release, plasma level, and renal receptors have been described in humans and/or animals with cirrhosis and ascites, little is known about the ANF hormonal system in cirrhosis without ascites. The aim of this study was to examine the ANF hormonal system in an animal model of cirrhosis to determine whether compensated cirrhosis is associated with changes in the ANF hormonal system. Pair-fed rats were studied 5-7 weeks after either sham surgery or bile duct ligation. Bile duct-ligated (BDL) rats had elevated portal pressure and cirrhosis but did not have ascites. ANF messenger RNA levels were increased onefold in the atria of BDL rats. Sham-operated and BDL rats had similar plasma ANF levels. Competitive binding inhibition studies of isolated glomeruli showed a single class of receptors in sham-operated and BDL rats. The equilibrium dissociation constant was similar in sham-operated (0.51 nmol/L) and BDL (0.63 nmol/L) rats. Glomerular ANF receptor density increased significantly in BDL rats. Cyclic guanosine monophosphate generation in isolated glomeruli in response to 100 nmol/L ANF decreased slightly but not significantly in BDL rats. It was concluded that the ANF hormonal system is altered in cirrhosis without ascites; atrial messenger RNA level and glomerular ANF receptor density are increased.
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PMID:Atrial natriuretic factor in experimental cirrhosis in rats. 145 99

The discovery of atrial natriuretic peptide (ANP) has modified our current understanding of the regulation of sodium metabolism. This peptide, of which the second messenger is cyclic guanosine monophosphate (cyclic GMP), is released by the atrial myocytes in response to increased atrial stretch and has for essential function to diminish the venous return to the heart. Radioimmunoassays have demonstrated that plasma ANP and cyclic GMP levels are increased in various diseases such as congestive heart failure (CHF), renal insufficiency, and, to a lesser extent, diabetes mellitus and liver cirrhosis with ascites. Plasma ANP is of prognostic value in CHF and reflects the effective central volemia in renal failure so that its assay as well as that of plasma cyclic GMP seem of interest in these diseases. Further studies are needed to assess the pathophysiological significance of ANP in diabetes mellitus and cirrhosis, and to define the indications of the treatment by enkephalinase inhibitors which increase endogenous ANP levels by lowering the catabolism of this hormone.
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PMID:Current indications of plasma atrial natriuretic peptide measurements in human diseases. 215 73

To clarify the involvement of atrial natriuretic peptide (ANP) in the pathogenesis of liver cirrhosis, we measured plasma ANP in patients with various stages of cirrhosis and in age-matched normal subjects. Urinary cyclic guanosine monophosphate (cGMP) was also measured as a marker of active biological ANP. In addition, effects of exogenous synthetic human ANP (0.5 micrograms/kg) on renal functions were examined in normal subjects and in cirrhotics without ascites or with mild ascites. Plasma ANP levels were not significantly different among these 3 groups. Urinary cGMP concentrations were significantly higher in both cirrhotics without ascites and cirrhotics with mild ascites, (340 pmol/ml, P less than 0.05 and 496 pmol/ml, P less than 0.01 respectively) than normal subjects (95 pmol/ml). In normal subjects, marked increases in urinary volume (UV), sodium excretion (UNaV), fraction excretion of sodium (FENa) and free water clearance (CH2O) were induced after ANP infusion, and significant recoveries were subsequently observed in these parameters. However, in cirrhotics, the responses to ANP infusion of UV, FENa and CH2O were far less dramatic. The response of UV, UNaV and FENa in cirrhotics with mild ascites was delayed compared to cirrhotics without ascites. These results suggest that the blunted natriuretic responsiveness to ANP is contributory to the pathogenesis of initial sodium retention in cirrhotics.
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PMID:Atrial natriuretic peptide in liver cirrhosis with mild ascites. 216 95

The correlation of collagen metabolism to liver contents of cyclic AMP and GMP as well as blood level of hormones was investigated in 105 patients with chronic hepatitis and liver cirrhosis. In patients with active hepatitis and cirrhosis showing the highest intensity of collagen metabolism there appeared elevated levels of cyclic AMP, somatotropic hormone and insulin against low levels of hydrocortisone and thyroxin. The relations between characteristics of plasma protein-bound oxyproline (PBOP), circadian oxyprolinuria and regulatory mechanisms under study suggest a competitive control of hepatic connective tissue metabolism maintained by hormones via cyclase systems. In high levels of blood PBOP and low ones of hydrocortisone, glucocorticoids unlike D-penicillamine promoted inhibition of liver collagen synthesis.
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PMID:[Various characteristics of collagen metabolism in patients with chronic diseases of the liver]. 262 62

Plasma immunoreactive alpha-human atrial natriuretic peptide (ANP) was measured in six cirrhotic patients with massive refractory ascites, under strict metabolic conditions, while they were receiving a 20-meq sodium diet, both before and at two-hour intervals for eight hours following peritoneovenous shunting (PVS). The mean preoperative level of ANP was 75 +/- 18 pg/ml, which was found to be significantly higher than the normal range for this laboratory (8 to 24 pg/ml) (p less than 0.05). This value was also significantly higher than the value of 21 +/- 5 pg/ml (p less than 0.05) obtained in six patients with cirrhosis but without ascites. Following shunt insertion, an immediate natriuresis and diuresis were observed in five of the six cirrhotic patients with refractory ascites. In these five, right atrial pressure and ANP rose immediately, followed by a rise in the level of urinary cyclic guanosine monophosphate. The sixth subject had a delayed rise in right atrial pressure, and correspondingly the rise in ANP, the diuresis, and natriuresis were delayed. The changes in ANP following PVS were positively correlated with changes in right atrial pressure (p less than 0.05), urinary cyclic guanosine monophosphate (p less than 0.05), urinary sodium excretion (p less than 0.05), and urine volume (p less than 0.01). These results suggest that ANP may be important in mediating the acute response to PVS.
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PMID:Acute effects of peritoneovenous shunting on plasma atrial natriuretic peptide in cirrhotic patients with massive refractory ascites. 282 65

Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) were assayed in ascitic fluid from 27 patients with ovarian carcinoma and 23 patients with liver cirrhosis. The value of these cyclic nucleotides was correlated with standard methods for the clinical evaluation of tumors. No change in the cGMP levels was found in either of these groups. The cAMP content, however, was increased in 23 of the 27 cases of ovarian carcinoma. The high cAMP level was correlated with the cytological findings in only 13 (48.1%) of these cases.
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PMID:Cyclic nucleotides in ascites from ovarian carcinoma. 407 26

1. There is currently considerable interest in the role of locally produced vasodilators such as nitric oxide and adenosine in the pathogenesis of the peripheral vasodilatation of cirrhosis. However, the signal transduction pathways involving guanylate cyclase and adenylate cyclase have not been clearly delineated in the isolated blood vessel. 2. We therefore aimed to examine the in vitro vasorelaxant effects of the endothelium-dependent dilator bethanechol, the endothelium-independent dilator sodium nitroprusside and adenosine, as drugs that work via activation of guanylate and adenylate cyclases, in isolated aortic and superior mesenteric arterial rings from cirrhotic and control rats. 3. Cirrhosis was induced by chronic bile duct ligation and section of 24-28 days' duration, while controls underwent sham operation. The vessels were precontracted with the alpha 1-adrenoceptor agonist phenylephrine, then relaxed by incremental doses of the three drugs. 4. Marked attenuation of vasoconstriction induced by phenylephrine in isolated aortic and mesenteric arterial rings from cirrhotic rats compared with the control vessels was observed. 5. There were no significant differences in relaxation between the cirrhotic and control vessels to the three drugs. We conclude that in vitro vasodilatory responses mediated through signal transduction pathways involving guanylate cyclase and adenylate cyclase remain unchanged in a rat model of biliary cirrhosis.
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PMID:Vasodilatory responses of isolated arteries of cirrhotic rats. 749 16

To test the hypothesis that diminished sodium delivery to the distal tubular site of atrial natriuretic peptide (ANP) action accounts for renal ANP resistance in cirrhosis, 12 cirrhotic patients with ascites were studied at baseline and during the infusion of ANP alone (0.15 micrograms/kg/min), mannitol alone (4 g/hr), and ANP plus mannitol for 3 hours each. Distal tubular sodium delivery, as assessed by lithium clearance, was increased during the infusion of mannitol (13.8 +/- 3.4 to 23.7 +/- 5.7 mL/min; P < .05) and during the ANP plus mannitol infusion (13.8 +/- 3.4 to 28.5 +/- 6.3 mL/min; P < .001) in 6 patients, subsequently termed "responders." Both responders and nonresponders were resistant to the natriuretic effect of ANP infused alone, and mannitol alone did not produce an increase in urinary sodium excretion. However, in responders, the mannitol-induced increase in distal tubular sodium delivery resulted in a fivefold increase in urinary sodium excretion during ANP infusion (29 +/- 6 to 154 +/- 40 mumol/min, P < .01). Urinary cyclic guanosine monophosphate (cGMP) excretion increased significantly and to a similar extent during ANP and ANP plus mannitol in all 12 patients, supporting the active biological responsiveness of renal ANP receptors. Unlike responders, nonresponders showed a significant decrease in arterial blood pressure and an increase in plasma renin activity during ANP plus mannitol, consistent with worsened arterial underfilling caused by ANP-induced vasodilation. Thus, the present results support the hypothesis that diminished distal tubular sodium delivery is a major factor contributing to ANP resistance in cirrhosis.
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PMID:Reversal of atrial natriuretic peptide resistance by increasing distal tubular sodium delivery in patients with decompensated cirrhosis. 765 77

Arterial vasodilation is considered to be the key factor in the development of sodium and water retention leading to ascites formation in cirrhosis. To determine if nitric oxide (NO) is involved in the pathogenesis of arterial vasodilation in cirrhosis, we measured the concentration of cyclic guanosine monophosphate (cGMP), the second messenger of NO, in arterial tissue from rats with carbon tetrachloride-induced cirrhosis. Aortic cGMP concentration was markedly increased in cirrhotic rats, particularly in those with ascites (ascites, 826 +/- 70; no ascites, 597 +/- 48; controls, 331 +/- 25 fmol/mg, ANOVA F = 23.1, P < .0001), and correlated inversely with arterial pressure (r = -.56, P < .0001) and systemic vascular resistance (r = -.69, P = .014) and directly with cardiac index (r = .74, P < .01). The chronic administration of the NO synthesis inhibitor NG-nitro-L-arginine-methyl-ester (L-NAME) (10 mg/kg/day for 7 days) induced a marked reduction in aortic cGMP concentration in cirrhotic rats with ascites to similar values obtained in L-NAME-treated control rats (86 +/- 14 vs. 89 +/- 8 fmol/mg, respectively, NS), indicating that the high-aortic cGMP content in cirrhotic rats was caused by an increased NO synthesis. Mean arterial pressure after L-NAME treatment increased to similar values in both groups of animals. These results suggest that in cirrhosis there is an increased vascular production of NO that may play a role in the pathogenesis of arterial vasodilation.
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PMID:Increased aortic cyclic guanosine monophosphate concentration in experimental cirrhosis in rats: evidence for a role of nitric oxide in the pathogenesis of arterial vasodilation in cirrhosis. 776 8

Cirrhotic rats have an increased susceptibility to ethanol-induced gastric injury, related to an inability to mount a defensive gastric hyperemic response to luminal irritants, and associated with an impaired reactivity of the gastric microcirculation to nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)-dependent vasodilators. Whether this hyporesponsiveness is in some way related to depressed prostaglandin synthesis by the stomach of cirrhotic rats is not clear. The aims of this study were to evaluate the role of NO and prostaglandins in the regulation of the gastric microcirculation under resting conditions and in response to administration of sodium nitroprusside, as well as to investigate the mechanisms of the hyporesponsiveness of the gastric microcirculation to nitrovasodilators. Cirrhosis was induced in rats by bile duct ligation, and controls had sham-operation. NG-nitro-L-arginine-methyl-ester (L-NAME) and indomethacin administration produced a greater reduction in gastric blood flow in cirrhotic rats than controls. Indomethacin pretreatment almost completely abolished the responsiveness to sodium nitroprusside (NaNP) in cirrhotic rats, while not affecting controls. Long-term administration of misoprostol to cirrhotic rats restored to normal the responsiveness to NaNP, whereas long-term administration of aspirin to healthy rats resulted in a hyporesponsiveness of the gastric microcirculation to NaNP similar to that seen in cirrhotic rats. We conclude that there are interactions between NO and prostaglandins in regulating gastric blood flow in both healthy and cirrhotic rats. The hyporesponsiveness of the gastric microcirculation of cirrhotic rats to a nitrovasodilator may occur as a consequence of prolonged depression of gastric prostaglandin synthesis.
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PMID:Prostaglandins modulate the responsiveness of the gastric microcirculation of sodium nitroprusside in cirrhotic rats. 855 31


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