AIM:Adrenomedullin (ADM) is a potent vasodilator peptide. ADM and nitric oxide (NO) are produced in vascular endothelial cells.Increased ADM level has been linked to hyperdynamic circulation and arterial vasodilatatio...AIM:Adrenomedullin (ADM) is a potent vasodilator peptide. ADM and nitric oxide (NO) are produced in vascular endothelial cells.Increased ADM level has been linked to hyperdynamic circulation and arterial vasodilatation in cirrhotic portal hypertension (CPH).The role of ADM in non-cirrhotic portal hypertension (NCPH) is unknown,plasma ADM levels were studied in patients with NCPH,compensated and decompensated cirrhosis in order to determine its contribution to portal hypertension (PH) in these groups. METHODS:There were 4 groups of subjects.Group 1 consisted of 27 patients (F/M:12/15) with NCPH due to portal and/or splenic vein thrombosis (mean age:41±12 years),group 2 consisted of 14 patients (F/M:6/8) with compensated (Child-Pugh A) cirrhosis (mean age:46±4), group 3 consisted of 16 patients (F/M:6/10) with decompensated (Child-Pugh C) cirrhosis (mean age:47±12). Fourteen healthy subjects (F/M:6/8) (mean age:44±8) were used as controls in Group 4.ADM level was measured by ELISA.NO was determined as nitrite/nitrate level by chemoluminescence. RESULTS:ADM level in Group 1 (236±61.4 pg/mL) was significantly higher than that in group 2 (108.4±28.3 pg/mL) and group 4 (84.1±31.5 pg/mL) (both P<0.0001) but was lower than that in Group3 (324±93.7 pg/mL) (P=0.002).NO level in group 1 (27±1.4 μmol/L) was significantly higher than that in group 2 (19.8±2.8 μmol/L) and group 4 (16.9±1.6 μmol/L) but was lower than that in Group 3 (39±3.6 μmol/L) (for all three P<0.0001).A strong correlation was observed between ADM and NO levels (r=0.827,P<0.0001). CONCLUSION:Adrenomedullin and NO levels were high in both non-cirrhotic and cirrhotic portal hypertension and were closely correlated,Adrenomedullin and NO levels increased proportionally with the severity of cirrhosis,and were significantly higher than those in patients with NCPH. Portal hypertension plays an important role in the increase of ADM and NO.Parenchymal damage in cirrhosis may contribute to the increase in these parameters.展开更多
The two most widely used experimental models of advanced liver disease are the administration of carbon tetrachloride, and common bile duct ligation (BDL), however, neither has been systematically evaluated as a model...The two most widely used experimental models of advanced liver disease are the administration of carbon tetrachloride, and common bile duct ligation (BDL), however, neither has been systematically evaluated as a model of hepatorenal syndrome (HRS). The BDL model in rats, studied at diverse time points, induced a progressive renal dysfunction without structural changes in the kidney. The authors concluded that BDL is a good model for further studies of HRS and its treatment. However, the renal impairment observed at the acute phase of the BDL model is based on a different pathophysiology than that of HRS. Specifi cally, in acute obstructive jaundice, cholemia predominates over parenchymal liver disease (reversible at this stage without portal hypertension or cirrhosis) and independently induces negative inotropic and chronotropic effects on the heart, impaired sympathetic vasoconstriction response and profound natriuresis and diuresis that might lead to volume depletion. In addition, systemic endotoxemia contributes to the prerenal etiology of renal impairment and promotes direct nephrotoxicity and acute tubular necrosis. On the other hand, the renal failure observed in the chronic BDL model (with development of biliary cirrhosis, portal hypertension and ascites) shares pathophysiological similarities with HRS, but the accordance of the chronic BDL model to the diagnostic criteria of HRS (e.g. absence of spontaneous bacterial peritonitis, no renal function improvement after plasma volume expansion) should have been confirmed. In conclusion, we think that the BDL model is not suitable for the study of the natural history of HRS, but the chronic BDL model might be valid for the study of established HRS and its potential therapies.展开更多
Ascites is the most common complication related to cirrhosis and is associated with increased morbidity and mortality.Ascites is a consequence of the loss of compensatory mechanisms to maintain the overall effective a...Ascites is the most common complication related to cirrhosis and is associated with increased morbidity and mortality.Ascites is a consequence of the loss of compensatory mechanisms to maintain the overall effective arterial blood volume due to worsening splanchnic arterial vasodilation as a result of clinically significant portal hypertension.In order to maintain effective arterial blood volume,vasoconstrictor and antinatriuretic pathways are activated,which increase overall sodiumand fluid retention.As a result of progressive splanchnic arterial vasodilation,intestinal capillary pressure increases and results in the formation of protein-poor fluid within the abdominal cavity due to increased capillary permeability from the hepatic sinusoidal hypertension.In some patients,the fluid can translocate across diaphragmatic fenestrations into the pleural space,leading to hepatic hydrothorax.In addition,infectious complications such as spontaneous bacterial peritonitis can occur.Eventually,as the liver disease progresses related to higher portal pressures,loss of a compensatory cardiac output and further splanchnic vasodilation,kidney function becomes compromised fromworsening renal vasoconstriction as well as the development of impaired solute-free water excretion and severe sodium retention.Thesemechanisms then translate into significant clinical complications,such as refractory ascites,hepatorenal syndrome and hyponatremia,and all are linked to increased short-termmortality.Currently,liver transplantation is the only curative option for this spectrumof clinical manifestations but ongoing research has led to further insight on alternative approaches.This review will further explore the current understanding on the pathophysiology andmanagement of ascites as well as expand on two advanced clinical consequences of advanced liver disease,refractory ascites and hyponatremia.展开更多
文摘AIM:Adrenomedullin (ADM) is a potent vasodilator peptide. ADM and nitric oxide (NO) are produced in vascular endothelial cells.Increased ADM level has been linked to hyperdynamic circulation and arterial vasodilatation in cirrhotic portal hypertension (CPH).The role of ADM in non-cirrhotic portal hypertension (NCPH) is unknown,plasma ADM levels were studied in patients with NCPH,compensated and decompensated cirrhosis in order to determine its contribution to portal hypertension (PH) in these groups. METHODS:There were 4 groups of subjects.Group 1 consisted of 27 patients (F/M:12/15) with NCPH due to portal and/or splenic vein thrombosis (mean age:41±12 years),group 2 consisted of 14 patients (F/M:6/8) with compensated (Child-Pugh A) cirrhosis (mean age:46±4), group 3 consisted of 16 patients (F/M:6/10) with decompensated (Child-Pugh C) cirrhosis (mean age:47±12). Fourteen healthy subjects (F/M:6/8) (mean age:44±8) were used as controls in Group 4.ADM level was measured by ELISA.NO was determined as nitrite/nitrate level by chemoluminescence. RESULTS:ADM level in Group 1 (236±61.4 pg/mL) was significantly higher than that in group 2 (108.4±28.3 pg/mL) and group 4 (84.1±31.5 pg/mL) (both P<0.0001) but was lower than that in Group3 (324±93.7 pg/mL) (P=0.002).NO level in group 1 (27±1.4 μmol/L) was significantly higher than that in group 2 (19.8±2.8 μmol/L) and group 4 (16.9±1.6 μmol/L) but was lower than that in Group 3 (39±3.6 μmol/L) (for all three P<0.0001).A strong correlation was observed between ADM and NO levels (r=0.827,P<0.0001). CONCLUSION:Adrenomedullin and NO levels were high in both non-cirrhotic and cirrhotic portal hypertension and were closely correlated,Adrenomedullin and NO levels increased proportionally with the severity of cirrhosis,and were significantly higher than those in patients with NCPH. Portal hypertension plays an important role in the increase of ADM and NO.Parenchymal damage in cirrhosis may contribute to the increase in these parameters.
文摘The two most widely used experimental models of advanced liver disease are the administration of carbon tetrachloride, and common bile duct ligation (BDL), however, neither has been systematically evaluated as a model of hepatorenal syndrome (HRS). The BDL model in rats, studied at diverse time points, induced a progressive renal dysfunction without structural changes in the kidney. The authors concluded that BDL is a good model for further studies of HRS and its treatment. However, the renal impairment observed at the acute phase of the BDL model is based on a different pathophysiology than that of HRS. Specifi cally, in acute obstructive jaundice, cholemia predominates over parenchymal liver disease (reversible at this stage without portal hypertension or cirrhosis) and independently induces negative inotropic and chronotropic effects on the heart, impaired sympathetic vasoconstriction response and profound natriuresis and diuresis that might lead to volume depletion. In addition, systemic endotoxemia contributes to the prerenal etiology of renal impairment and promotes direct nephrotoxicity and acute tubular necrosis. On the other hand, the renal failure observed in the chronic BDL model (with development of biliary cirrhosis, portal hypertension and ascites) shares pathophysiological similarities with HRS, but the accordance of the chronic BDL model to the diagnostic criteria of HRS (e.g. absence of spontaneous bacterial peritonitis, no renal function improvement after plasma volume expansion) should have been confirmed. In conclusion, we think that the BDL model is not suitable for the study of the natural history of HRS, but the chronic BDL model might be valid for the study of established HRS and its potential therapies.
文摘Ascites is the most common complication related to cirrhosis and is associated with increased morbidity and mortality.Ascites is a consequence of the loss of compensatory mechanisms to maintain the overall effective arterial blood volume due to worsening splanchnic arterial vasodilation as a result of clinically significant portal hypertension.In order to maintain effective arterial blood volume,vasoconstrictor and antinatriuretic pathways are activated,which increase overall sodiumand fluid retention.As a result of progressive splanchnic arterial vasodilation,intestinal capillary pressure increases and results in the formation of protein-poor fluid within the abdominal cavity due to increased capillary permeability from the hepatic sinusoidal hypertension.In some patients,the fluid can translocate across diaphragmatic fenestrations into the pleural space,leading to hepatic hydrothorax.In addition,infectious complications such as spontaneous bacterial peritonitis can occur.Eventually,as the liver disease progresses related to higher portal pressures,loss of a compensatory cardiac output and further splanchnic vasodilation,kidney function becomes compromised fromworsening renal vasoconstriction as well as the development of impaired solute-free water excretion and severe sodium retention.Thesemechanisms then translate into significant clinical complications,such as refractory ascites,hepatorenal syndrome and hyponatremia,and all are linked to increased short-termmortality.Currently,liver transplantation is the only curative option for this spectrumof clinical manifestations but ongoing research has led to further insight on alternative approaches.This review will further explore the current understanding on the pathophysiology andmanagement of ascites as well as expand on two advanced clinical consequences of advanced liver disease,refractory ascites and hyponatremia.
