Tryglycylvasopressin-reduced portal and systemic concentrations of serum bile acids after exogenous chenodeoxycholic acid load in rats as a reflection of reduced splanchnic blood flow

The effect of triglycylvasopressin (TGVP) on the absorption of chenodeoxycholic acid (CDCA) was investigated in three groups of six rats (controls, CDCA, CDCA + TGVP) through the evaluation of portal and caval serum bile acids (SBA) concentrations after an oral load with CDCA to investigate whether changes in this parameter reflect variations in splanchnic blood flow induced by a vasoconstrictor. The results indicate that CDCA was absorbed and led to a significant increase in SBA. This increase was reduced by TGVP administration: portal blood 380.0 +/- 61.2 vs 279.7 +/- 45.3; caval blood 151.8 +/- 45.7 vs 41.7 +/- 12.5 (mumol/l; mean +/- s.d.). This suggests that variations in SBA concentrations could reflect changes in splanchnic circulation.     

Propranolol and haemodynamic response in cirrhosis.

In the present study, we compared cirrhotic patients who had a decrease in the hepatic venous pressure gradient after propranolol intake to patients without a decrease. Twenty patients with cirrhosis and oesophageal varices were investigated during hepatic vein catheterization before and 90 min after an oral dose of 80 mg propranolol. The hepatic venous pressure gradient decreased by 12.6% (19.0 +/- 4.7 to 16.3 +/- 3.6 mm Hg, p less than 0.05). Eight (40%) out of 20 patients had a decrease of less than 10% in protal pressure (non-responders). Responders had a higher baseline cardiac index than non-responders (3.79 +/- 0.74 vs. 2.83 +/- 0.53 1.min-1.m-2; p less than 0.01). No difference in the effect of propranolol on portal pressure was observed between patients with or without ascites, or between Child-Turcotte A, B, and C class patients. Our results suggest that cirrhotic patients who respond to oral propranolol with a decrease in portal pressure are more hyperdynamic than those without a significant fall in portal pressure.     

Enhancement of portal pressure reduction by the association of isosorbide-5-mononitrate to propranolol administration in patients with cirrhosis

This study investigated whether oral doses of isosorbide-5-mononitrate, a preferential venous dilator that decreases portal pressure, could enhance the effects of propranolol on portal hypertension. Taking part in the study were 28 patients with cirrhosis and portal hypertension. Twenty patients (group 1) had hemodynamic measurements in baseline conditions after beta-blockade by intravenous administration of propranolol and after receiving oral doses of isosorbide-5-mononitrate. The remaining eight patients (group 2) were given oral isosorbide-5-mononitrate while receiving chronic propranolol therapy. In group 1, propranolol significantly reduced portal pressure (estimated as the gradient between wedged and free hepatic venous pressures) from 21.5 +/- 3.9 to 18.6 +/- 4.2 mm Hg (-13.7%, p less than 0.001), azygos blood flow (-38%, p less than 0.001), hepatic blood flow (-12.8%, p less than 0.05), cardiac output (-24.5%, p less than 0.001) and heart rate (-18.4%, p less than 0.001) without significant changes in mean arterial pressure. Addition of oral isosorbide-5-mononitrate caused a further and marked fall in portal pressure (to 15.7 +/- 3.1 mm Hg, p less than 0.001), without additional changes in azygos blood flow but with significant additional reductions in hepatic blood flow (-15.5%, p less than 0.05), cardiac output (-11.5%, p less than 0.001) and mean arterial pressure (-22%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of propranolol on portosystemic collateral circulation in patients with cirrhosis

Propranolol has been demonstrated to be effective in lowering portal pressure in cirrhotic patients. This effect is mediated by a reduction of splanchnic arterial inflow and a consequent decrease of portal vein and portocollateral blood flow. Although experimental studies suggest a direct effect of the drug on portocollateral circulation, little information exists about relative flow changes occurring in the portal vein and in collateral veins feeding esophageal varices. This study addressed the problem in 12 cirrhotic patients selected on the basis of feasibility of Doppler flowmetry in both the portal and left gastric veins. Caliber, flow velocity and flow volume in both vessels were measured by Doppler ultrasound before and at 60, 120 and 180 min after an oral dose of 40 mg propranolol, together with heart rate and mean arterial pressure. A significant decrease in heart rate (-17.6% +/- 1.1%, p less than 0.001) and mean arterial pressure (-10.6% +/- 0.9%, p less than 0.005) confirmed effective beta-blockade. Baseline flow velocity was significantly lower in the portal vein than in the left gastric vein (12.4 +/- 0.6 vs. 15.4 +/- 1.5 cm/sec, p less than 0.05). Maximal hemodynamic effect was reached at 120 min after administration of propranolol. The vessel caliber did not change significantly. Flow velocity fell from 12.4 +/- 0.6 to 10.4 +/- 0.7 cm/sec in the portal vein (p less than 0.05) and from 15.4 +/- 1.5 to 11.1 +/- 0.9 cm/sec in the left gastric vein (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Beta-blockade with propranolol and hepatic artery blood flow in patients with cirrhosis

In patients with cirrhosis and portal hypertension, propranolol administration reduces heart rate and cardiac output and diminishes portal pressure and collateral blood flow. However, there is little information on the possible effects of propranolol on hepatic artery blood flow. The present study addressed this question in 12 cirrhotic patients with end-to-side portacaval shunt, in whom all of the liver blood flow represents the hepatic artery blood flow. Hepatic artery blood flow (continuous infusion of indocyanine green), cardiac output (thermal dilution), heart rate and mean arterial pressure were measured before and 20 min after the intravenous infusion of 10 to 15 mg of propranolol. beta-Adrenergic blockade caused a significant reduction of cardiac output (from 9.1 +/- 2.1 to 7.1 +/- 1.4 liters per min, p less than 0.001) (mean +/- S.D.) and heart rate (from 85 +/- 10 to 71 +/- 7 beats per min, p less than 0.001), and a significant increase of systemic vascular resistance (from 9.0 +/- 2.1 to 11.7 +/- 2.7 mmHg per liter per min, p less than 0.001), whereas mean arterial pressure did not change (77 vs. 78 mmHg). Propranolol significantly reduced hepatic artery blood flow (from 0.65 +/- 0.20 to 0.55 +/- 0.14 liters per min, p less than 0.01). However, reduction of hepatic artery blood flow (-12.9 +/- 7.3%) was significantly less than reduction of cardiac output (-21.1 +/- 5.2%, p less than 0.01). As a result, the fraction of the cardiac output delivered to the liver was significantly greater after propranolol (8.0 +/- 1.7%) than before (7.3 +/- 1.7%, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of portal vein velocity and the hepatic venous pressure gradient in assessing the acute portal hemodynamic response to propranolol in patients with cirrhosis

OBJECTIVE: The aim of this prospective study was to compare noninvasive Doppler sonography and invasive measurement of the hepatic venous pressure gradient (HVPG) to determine the acute portal hemodynamic response to propranolol in patients with liver cirrhosis. METHODS: In a blinded study design, portal vein velocity (PVV) and HVPG were simultaneously assessed in 11 cirrhotic patients for 4 h after oral ingestion of 40 mg propranolol. RESULTS: Both HVPG (17.2% +/- 4.3%, p < 0.0001) and PVV (15.6% +/- 2.1%, p < 0.0002) showed a highly significant reduction during the study period versus baseline. Based on HVPG measurements, four patients (36%) were classified as nonresponders. These patients had a significantly lower PVV reduction compared to the responders (responders: 18.8% +/- 2.0% vs nonresponders: 10.0% +/- 2.1%, p < 0.05). Nonresponders were identified by Doppler sonography with a sensitivity of 1.0, specificity of 0.86, and positive predictive value of 0.9 when a threshold of 20% PVV reduction 120 min after drug intake was applied. CONCLUSIONS: Doppler sonography is a useful tool for assessment of the acute portal hemodynamic effect of propranolol. To distinguish portal hemodynamic nonresponders from responders to propranolol, PVV measurements should be carried out 2 h after drug administration, and PVV reduction should be not <20% in propranolol responders.     

Discrepancy between portal pressure and systemic hemodynamic changes after incremental doses of propranolol in awake portal hypertensive rats

The effects of increasing doses of propranolol were studied in awake portal hypertensive rats in order to elucidate the relative effects of the beta-blocker on systemic and splanchnic circulation. Hemodynamic responses to 0.1, 0.2 and 0.4 mg per min infusions of propranolol were compared with placebo in awake rats with portal hypertension due to portal vein stenosis. Heart rate significantly and progressively decreased from 356 +/- 13 to 293 +/- 10 beats per min (mean +/- S.E.). Cardiac output significantly decreased from 54 +/- 3 to 42 +/- 3 ml per min per 100 gm body weight at the highest dose. Significant decrease in portal tributary blood flow from 27 +/- 1 to 18 +/- 1 ml per min, at 0.4 mg per min dose, was due not only to the decrease in cardiac output but also to a significant increase in portal tributary vascular resistance from 269 +/- 17 to 368 +/- 31 dyne per sec per cm5 x 10(3). However, portal pressure showed only an insignificant decrease from 14.9 +/- 1.1 to 14.1 +/- 1.4 mmHg. The reduction in portal pressure being minimal, in spite of a significant decrease in portal tributary blood flow, is explained by an increase in combined hepatic and collateral resistance from 44 +/- 2 to 66 +/- 4 dyne per sec per cm5 x 10(3), p less than 0.05, at 0.4 mg per min dose. We conclude that the systemic and splanchnic effects of propranolol show discrepancy at two levels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Propranolol compared with propranolol plus isosorbide-5-mononitrate for portal hypertension in cirrhosis. A randomized controlled study

OBJECTIVE: To investigate whether isosorbide-5-mononitrate (Is-5-Mn) given with propranolol reduces hepatic portal pressure more than does propranolol alone in patients with cirrhosis. DESIGN: A randomized controlled trial. PATIENTS: Fifty patients with cirrhosis and esophageal varices entered and 42 completed the study. INTERVENTION: Twenty-one patients received oral propranolol at increasing doses until their resting heart rate was reduced by 25%, and 21 patients received oral propranolol (on the same schedule) plus oral Is-5-Mn, 40 mg twice a day. MEASUREMENTS: Hepatic vein pressure gradient, liver function, and splanchnic and systemic hemodynamics before and after 3 months of continuous therapy. MAIN RESULTS: At 3 months, the hepatic venous pressure gradient decreased more (P less than 0.01) in patients given propranolol plus Is-5-Mn (19%, from 18.4 +/- 3.9 to 14.9 +/- 3.8 mm Hg; 95% CI, -2.4 to -4.5 mm Hg) than in those given propranolol alone (10%, from 18.2 +/- 3.5 to 16.3 +/- 3.1 mm Hg; CI, -1.1 to -2.7 mm Hg). The hepatic venous pressure gradient decreased by more than 20% of the baseline value in 10% of patients receiving propranolol, but in 50% of patients receiving combined therapy (P less than 0.02). There were statistically significant decreases in hepatic blood flow and the intrinsic clearance of indocyanine green after propranolol therapy, but not after combined therapy. The treatments caused similar reductions in azygos blood flow and cardiac output. CONCLUSIONS: The long-term combined administration of propranolol plus Is-5-Mn reduces portal pressure more than propranolol alone without adverse effects on hepatic perfusion and liver function. Whether this greater hemodynamic effect translates into better clinical efficacy should be determined in randomized controlled trials.     

Mechanisms of a clonidine-induced decrease in portal pressure in normal and cirrhotic conscious rats

The effects of clonidine on portal pressure and splanchnic blood flow were studied in conscious rats with sinusoidal portal hypertension due to cirrhosis induced by bile duct ligation. In cirrhotic and sham-operated rats, clonidine (20 micrograms per kg body weight, intravenously) significantly reduced portal, pressure from 19.0 +/- 0.6 to 14.5 +/- 1.0 mmHg and from 9.8 +/- 0.9 to 7.3 +/- 0.5 mmHg, respectively. No significant change in systemic hemodynamics was observed. In cirrhotic rats, clonidine reduced portal pressure, probably by producing a significant increase in portal tributary vascular resistance leading to a 25% decrease in portal tributary blood flow (radioactive microsphere method). In sham-operated rats, clonidine reduced portal pressure presumably by decreasing hepatic portal vascular resistance, since no significant change in portal tributary blood flow was observed. In both groups, clonidine administration significantly decreased plasma noradrenaline concentration. Placebo administration produced neither significant hemodynamic nor significant plasma noradrenaline concentration change. These findings indicate that the sympathetic regulation of the splanchnic circulation is impaired in cirrhotic rats.     

Effects of molsidomine, a long acting venous dilator, on portal hypertension. A hemodynamic study in patients with cirrhosis.

The present study investigated the effects of molsidomine, a predominant venous dilator which, contrary to organic nitrates, does not produce pharmacological tolerance on splanchnic and systemic hemodynamics in patients with cirrhosis. Twenty-seven cirrhotic portal hypertensive patients were studied prior to and up to 2 h after the oral administration of 2 mg of molsidomine (n = 11), 4 mg of molsidomine (n = 8) or placebo (n = 8). Molsidomine caused a significant reduction in the hepatic venous pressure gradient. The mean decrease at 60 min was -6.8 +/- 9% after 2 mg (p less than 0.05) and -15.4 +/- 12% after 4 mg (p less than 0.01). The decrease in the hepatic venous pressure gradient was maintained at 120 min: -11% after 2 mg (p less than 0.05) and -19% with 4 mg (p less than 0.01). This was associated with mild changes in azygos blood flow and with a significant decrease in hepatic blood flow (-17%, p less than 0.05). There was a moderate reduction in mean arterial pressure (-12.6% after 2 mg and -13.2% after 4 mg, p less than 0.01), which was due to a reduction in cardiac output, without any significant fall in systemic vascular resistance. Placebo administration did not change systemic or hepatic hemodynamics. This study shows that molsidomine causes a significant and sustained reduction in portal pressure in patients with cirrhosis, suggesting the potential role of this agent in the treatment of portal hypertension.     

Acute administration of carvedilol is more effective than propranolol plus isosorbide-5-mononitrate in the reduction of portal pressure in patients with viral cirrhosis

OBJECTIVE: Propranolol is known to decrease portal pressure in cirrhotic patients with portal hypertension; however, a substantial number of patients do not respond to propranolol administration. The addition of isosorbide-5-mononitrate may enhance portal pressure reduction in patients receiving propranolol. Carvedilol is a nonselective beta-blocker with alpha(1)-adrenergic blocking activity. It has been shown to decrease portal pressure in cirrhotic patients. Additionally, carvedilol has a greater portal hypotensive effect than propranolol alone in patients with cirrhosis. The current study is aimed at comparing the acute hemodynamic effects of carvedilol with the effects of propranolol plus isosorbide-5-mononitrate in patients with viral cirrhosis. METHODS: Patients with viral cirrhosis were randomly assigned to receive an oral administration of carvedilol of 25 mg (n = 11) or an oral administration of propranolol 40 mg plus isosorbide-5-mononitrate 20 mg (n = 11). Hemodynamic values were measured at basal and 90 min after drugs administration. RESULTS: Both carvedilol and propranolol plus isosorbide-5-mononitrate significantly decreased cardiac index, heart rate, and HVPG. The magnitude of changes in HVPG observed between the basal and after drugs administration was greater in patients receiving carvedilol than in those receiving propranolol plus isosorbide-5-mononitrate (-18.6 +/- 3.6%vs-10.1 +/- 3.6%, p < 0.05). Hepatic blood flow increased following carvedilol administration but remained unchanged in patients receiving propranolol plus isosorbide-5-mononitrate. The magnitude of decrease in mean arterial pressure (MAP) did not differ between the two groups of patients. CONCLUSION: In our patients with viral cirrhosis, carvedilol is more effective than propranolol plus isosorbide-5-mononitrate in the reduction of HVPG. Carvedilol administration causes an increase in hepatic blood flow, but its systemic effects were similar to those of propranolol plus isosorbide-5-mononitrate.     

Propranolol decreases portal pressure without changing portocollateral resistance in cirrhotic rats

Propranolol decreases portal pressure by reducing portal blood inflow. Studies in rats with prehepatic portal hypertension due to portal vein stenosis (a model with extensive portosystemic shunting) have shown that propranolol increases the portocollateral resistance, which hinders the fall in portal pressure. The present study examined the effects of propranolol on splanchnic and systemic hemodynamics in rats with portal hypertension due to cirrhosis of the liver, a model which is characterized by mild portosystemic shunting. Two groups of rats with CCl4-induced cirrhosis were studied: the propranolol group (n = 8), which received a propranolol infusion of 2 mg per 15 min, and controls (n = 9), which received a placebo (saline) infusion. Hemodynamic measurements were done using radiolabeled microspheres. Propranolol-treated rats had significantly lower cardiac output (-31%) and heart rate (-26%) than controls (p less than 0.001). Hepatic artery flow was not modified by propranolol. Propranolol caused splanchnic vasoconstriction, manifested by increased splanchnic resistance (+57%) and by a significant fall in portal blood inflow (4.8 +/- 0.4 vs. 6.3 +/- 0.5 ml per min.100 gm in controls, p less than 0.05). In contrast with rats with prehepatic portal hypertension, propranolol did not increase portal resistance in cirrhotic rats [2.0 +/- 0.2 vs. 2.0 +/- 0.1 mmHg per ml per min.100 gm body weight (not significant)]. Hence, the fall in portal pressure (-19%) was expected from the decrease in portal inflow (-24%). These results suggest that increased portal resistance in rats with prehepatic portal hypertension may represent an intrinsic effect of propranolol on the portocollateral vessels, since beta-blockade does not modify portal vascular resistance in cirrhosis.     

Increased blood flow through the portal system in cirrhotic rats

Portal venous pressure is the result of the interplay between portal venous blood flow and the vascular resistance offered to that flow. Whether portal hypertension is maintained only by an increased portal venous resistance or also by an increased blood flow within the portal venous system is still open to speculation. To resolve these differences, splanchnic and systemic hemodynamics were evaluated in cirrhotic rats, induced by CCl4. Blood flow and portal-systemic shunting were measured by radioactive microsphere techniques. All cirrhotic rats had portal hypertension (portal venous pressure 13.5 +/- 1.1 vs. 9.0 +/- 0.5 mmHg, in normal control rats; p less than 0.01), but portal-systemic shunting in cirrhosis (31% +/- 13% vs. 0.2% +/- 0.02%; p less than 0.05) was variable, ranging from 1% to 97%. Portal venous inflow, the total blood flow within the portal system, was increased in cirrhotic rats (5.75 +/- 0.04 vs. 4.52 +/- 0.36 ml/min per 100 g; p less than 0.05). Total splanchnic arterial resistance was reduced in cirrhotic rats (3.3 +/- 0.2 vs. 5.8 +/- 0.5 dyn X s X cm-5 X 10(5); p less than 0.01). Portal venous resistance, however, was not abnormally elevated in cirrhotic rats (4.6 +/- 0.5 vs. 4.7 +/- 0.5 dyn X s X cm-5 X 10(4), p = NS). Splanchnic hemodynamics in cirrhotic rats demonstrate that portal hypertension is maintained, at least in part, by a hyperdynamic portal venous inflow. The hemodynamic data in cirrhotic rats provided evidence that supports the role of an increased portal blood flow in portal hypertension and gives a quantitative definition of splanchnic hemodynamics in intrahepatic portal hypertension.     

Acute and chronic hemodynamic effects of propranolol in unselected cirrhotic patients

Different and contradictory results concerning the use of propranolol in the treatment of portal hypertension have been reported. This study was designed to investigate the hemodynamic effects of short- and long-term administration of propranolol in portal hypertensive patients. Portal pressure, cardiac index, heart rate and blood pressure were obtained in 18 unselected alcoholic cirrhotic patients with esophageal varices before and 60 min after the oral administration of 40 mg propranolol and again after 106 +/- 35 days of continuous oral administration (mean dose = 158 +/- 63 mg per day). Baseline portal pressure was 21.7 +/- 7.2 mm Hg. It decreased after 60 min to 17.2 +/- 5.5 mm Hg (p less than 0.01) and after long-term administration of propranolol to 16.1 +/- 5.7 mm Hg (p less than 0.01). No decrease in portal pressure was noted in 9 of 18 (50%) patients after acute administration and 5 of 17 (30%) patients after long-term administration. Baseline cardiac index was 5.1 +/- 1.2 liters X min-1 X m-2. It decreased after 60 min to 3.9 +/- 1.4 liters X min-1 X m-2 (p less than 0.01) and to 3.6 +/- 1.0 liters X min-1 X m-2 after long-term administration (p less than 0.001). Baseline heart rate was 85 +/- 11 beats per min. It decreased after 60 min to 75 +/- 9 (p less than 0.001) and after long-term administration to 62 +/- 6 (p less than 0.001) beats per min. Baseline mean arterial pressure was 108 +/- 11 Hg. It decreased after 60 min to 97 +/- 14 mm Hg (p less than 0.01) and after long-term administration to 103 +/- 14 mm Hg (not statistically significant).(ABSTRACT TRUNCATED AT 250 WORDS)     

Acute effect of propranolol on splanchnic circulation in normal and portal hypertensive rats

Propranolol decreases portal venous pressure in patients with cirrhosis but no method is available in man to study the effect of this beta-blocker on splanchnic organ blood flow. Because in rats, the microsphere method allows evaluation of regional blood flow, the acute effect of propranolol on both splanchnic and systemic circulations was studied in normal rats and in rats with portal hypertension due to portal vein stenosis. Portal venous pressure significantly decreased during propranolol administration in normal (5.6 +/- 1.0-4.7 +/- 1.1 mm Hg; mean +/- SD) as well as in portal hypertensive rats (11.7 +/- 2.3-10.3 +/- 1.8 mm Hg). Propranolol slightly decreased cardiac output and arterial pressure in all rats. Portal tributary blood flow was significantly reduced by propranolol in normal rats (17.4 +/- 3.0-11.3 +/- 2.2 ml/min) and in portal hypertensive rats (23.7 +/- 5.0-16.6 +/- 3.3 ml/min). Accordingly vascular resistance of the different organs in the portal venous territory increased in these rats receiving propranolol. The percentage of the decrease in portal tributary blood flow was significantly more marked than the percentage of reduction in cardiac output in portal hypertensive rats but, in normal rats, these percentages were parallel. Hepatic arterial blood flow did not change or slightly increased and, consequently, hepatic arterial vascular resistance decreased. These findings further clarify the marked effects of propranolol on splanchnic circulation.     

Echo-Doppler evaluation of acute flow changes in portal hypertensive patients: flow velocity as a reliable parameter

In order to evaluate the behavior of the portal vein cross-sectional area during changes in portal flow, two groups of subjects were analyzed in two blinded cross-over studies using echo-Doppler flowmetry. The first group (I) consisted of 21 patients with cirrhosis and 16 controls. They received a standardized meal which is known to increase portal flow. The second group (II) consisted of 31 patients with cirrhosis who received a dose of propranolol which is known to decrease portal flow. In Group I, 30 min after the meal, the portal vein blood velocity increased by 35 +/- 6% (p less than 0.01) in cirrhotic patients and by 55 +/- 5% (p less than 0.01), in normal subjects. The portal vein cross-sectional area increased significantly in normal subjects (22 +/- 2%, p less than 0.01) but not in cirrhotic patients (4 +/- 2%, n.s.). In Group II, 2 h after propranolol, there was a significant decrease in portal blood velocity (-14 +/- 2%), whereas the portal vein cross-sectional area did not show any significant changes. These data demonstrate that, in portal hypersensitive patients, the portal area measured by echo-Doppler flowmetry can be assumed to be constant and hence its calculation to estimate changes in portal blood flow can be omitted. Therefore, the use of blood velocity alone is suggested to monitor acute changes in flow in portal hypertension using Doppler flowmetry. The elimination of the portal vein cross-sectional area measurement simplifies the quantitative calculation of portal hemodynamics and increases the reliability of the technique by avoiding a source of error.     

Effect and mechanism of action of isosorbide-5-mononitrate.

Nitrates have been shown to decrease portal pressure in cirrhotic patients with portal hypertension and this has been attributed to decreased portal venous resistance. We studied the effect and mechanism of action of oral administration of isosorbide-5-mononitrate (Is-5-Mn) (20 mg), which, unlike the dinitrate, does not require hepatic biotransformation to a vasoactive metabolite on portal and systemic haemodynamics in 11 patients with portal hypertension complicating cirrhosis. A significant reduction in portal pressure gradient (WHVP-FHVP) (from 23.9 (3.4) to 21.8 (3.4) mmHg: p less than 0.005) occurred 60 minutes after Is-5-Mn due entirely to a fall in WHVP, associated with decreased estimated liver blood flow (from 1940 (159) to 1639 (179) ml/min: p less than 0.05). Right atrial and pulmonary artery pressures and cardiac index fell significantly whilst mean arterial pressure remained unaffected. Heart rate and the calculated systemic vascular resistance index increased significantly. Significant correlations existed between the reduction in portal pressure gradient and fall in cardiac index (r = 0.65, p less than 0.05) and increase in systemic vascular resistance index (r = 0.72, p less than 0.02). The observed decrease in estimated liver blood flow, in association with an increase in systemic vascular resistance index, suggests that baroreceptor mediated splanchnic vasoconstriction may be one of the factors responsible for the fall in portal pressure, rather than portal venous dilatation.     

Effect of somatostatin on splanchnic hemodynamics in patients with cirrhosis of the liver and in normal subjects

The effect of somatostatin on splanchnic hemodynamics was determined in 8 patients with cirrhosis of the liver and in 18 normal subjects using arterial-hepatic-venous catheterization. Estimated hepatic blood flow determined by indocyanine green infusion was 1.36 +/- 0.23 L/min (+/- SEM) in patients with cirrhosis and remained unaffected during 30 min of somatostatin (250 microgram/h) administration. Wedged hepatic venous pressure which was elevated to 23 +/- 1.8 mmHg was also uninfluenced. In contrast to somatostatin, an infusion of vasopressin (12 U/h for 30 min) given to the same patients, lowered estimated blood flow by 28% (p < 0.05) and wedged hepatic venous pressure by 18% (p < 0.02). Arterial gastrin and insulin levels were lowered during somatostatin infusion by 33% (p < 0.02) and by 75% (p < 0.005), respectively. In contrast to the cirrhosis, infusion of 250 microgram/h somatostatin into normal subjects was associated with a decrease of estimated hepatic blood flow from 1.20 +/- 0.16 to 0.88 +/- 0.12 L/min (p < 0.01) representing a 27% decline. Arterial gastrin and insulin concentrations were lower (p < 0.01) than in cirrhosis, but the basal levels were lowered by somatostatin to a similar degree in both groups of patients. A higher dose of somatostatin (500 microgram/h) administered to normal subjects resulted in a similar decrease of gastrin and of estimated hepatic blood flow as that seen with 250 microgram/h, whereas a lower dose (125 microgram/h) decreased gastrin but failed to influence estimated hepatic blood flow. Thus, somatostatin at a dose which has been used in the treatment of acute peptic ulcer hemorrhage (250 microgram/h) failed to influence estimated hepatic blood flow and wegded hepatic venous pressure in patients with cirrhosis but lowered splanchnic blood flow in normal subjects. Assuming that this effect contributes to somatostatin's therapeutic efficacy, these results cast doubt on its potential value in the treatment of upper gastrointestinal bleeding of cirrhotics with portal hypertension.     

Serum uric acid levels in patients with cirrhosis: a reevaluation.

It has been reported that the serum uric acid levels in patients with cirrhosis were decreased compared with healthy subjects. These studies suggested that the lower serum uric acid levels in cirrhotic patients were attributed mainly to an increased effective vascular volume, and consequently to an excessive renal clearance of uric acid. However, the previous observations are challenged by a recent hypothesis for the pathogenesis of hyperdynamic circulation and formation of ascites in cirrhosis. The current study was undertaken to reevaluate serum uric acid levels in patients with cirrhosis. Ninety-eight cirrhotic patients with normal renal functions were included in this study. All biochemical and hemodynamic data were utilized for analysis. The mean serum uric acid level (mean, 6.1+/-1.2 mg/dL; range, 2.7-9.1 mg/dL) was higher than that of the age- and sex-matched healthy control subjects (mean, 5.5+/-1.3 mg/dL; range, 2.9-8.1 mg/dL; p = 0.018). Using multiple regression analysis it was determined that the serum uric acid level was not related to the severity of liver disease, cardiac index, systemic vascular resistance, and hepatic venous pressure gradient but was related closely to age (r = 0.210, p = 0.026) and effective renal plasma flow (r = -0.677, p < 0.0001). Compared with cirrhotic patients without ascites, those with ascites had a significantly higher serum uric acid level (6.7+/-1.6 mg/dL vs. 5.6+/-1.7 mg/dL, p < 0.05) and lower effective renal plasma flow (396+/-125 mL/min vs. 445+/-149 mL/min, p < 0.05). In conclusion, for cirrhotic patients with normal serum creatinine levels, the current study shows that the mean serum uric acid level is higher than that of healthy control subjects. It is not related to the severity of liver failure and systemic and portal hemodynamics, but is related closely to renal functions, especially the renal plasma flow.     

Lack of response to chenodeoxycholic acid in obese and non-obese patients. Role of cholesterol synthesis and possible response to ursodeoxycholic acid.

This paper describes seven patients with radiolucent gallstones in functioning gallbladders who did not respond to chenodeoxycholic acid (CDCA). Despite large doses (greater than or equal to 19 mg CDCA/kg/day), CDCA-rich bile (CDCA conjugates 70-97% of total biliary bile acids) and greater than or equal to one year's treatment, their fasting duodenal bile remained supersaturated with cholesterol and their gallstones did not dissolve. Five patients came to cholecystectomy, gallstone analysis and liver biopsy for measurement of hepatic cholesterogenesis (HMGCoAR activity). In three who stopped CDCA before surgery, the mean HMGCoAR (pmol/mg microsomal protein/min) of 50.2 was higher than in our untreated gallstone controls (32.2 +/- SEM 2.0; P less than 0.05). Two patients who took CDCA until surgery had a mean HMGCoAR of 33.5--more than twice that in CDCA-treated gallstone controls. These findings suggest that non-response to CDCA may be related to high or unsuppressed hepatic cholesterogenesis. In one patient who did not respond to CDCA, treatment with 19 mg ursodeoxycholic acid/kg/day did desaturate his bile.