Effect of bolus injection and continuous infusion of somatostatin on gastric perfusion in cirrhotic patients with portal-hypertensive gastropathy

A somatostatin analog improves tilt table tolerance by decreasing splanchnic vascular conductance

Splanchnic hemodynamics and tilt table tolerance were assessed after an infusion of placebo or octreotide acetate, a somatostatin analog whose vascular effects are largely confined to the splanchnic circulation. We hypothesized that reductions in splanchnic blood flow (SpBF) and splanchnic vascular conductance (SpVC) would be related to improvements in tilt table tolerance. In randomized, double-blind, crossover trials, hemodynamic variables were collected in 14 women and 16 men during baseline, 70° head-up tilt (HUT), and recovery. A repeated-measures analysis of variance was used to compare changes from baseline with respect to sex and condition. HUT elicited an increase in heart rate and decreases in mean arterial pressure, cardiac index, stroke index, and systemic vascular conductance. Additionally, SpVC and non-SpVC were lower during HUT. Octreotide reduced SpBF and SpVC and increased systemic vascular conductance and non-SpVC. Changes in SpBF and SpVC between supine and HUT were smaller in women (P < 0.05). Tilt table tolerance was increased after administration of octreotide [median tilt time: 15.7 vs. 37.0 min (P < 0.05) and 21.8 vs. 45.0 min (P < 0.05) for women and men, respectively]. A significant relationship existed between change (Δ) in SpBF (placebo-octreotide) and Δtilt time in women (Δtilt time = 2.5-0.0083 ΔSpBF, P < 0.01), but not men (Δtilt time = 3.41-0.0008 ΔSpBF, P = 0.59). In conclusion, administration of octreotide acetate improved tilt table tolerance, which was associated with a decrease in SpVC. In women, but not men, the magnitude of reduction in SpBF was positively associated with improvements in tilt tolerance.

The management of portal hypertension: rational basis, available treatments and future options

Variceal bleeding is the last step in a chain of events initiated by an increase in portal pressure, followed by the development and progressive dilation of varices until these finally rupture and bleed. This sequence of events might be prevented - and reversed - by achieving a sufficient decrease in portal pressure. A different approach is the use of local endoscopic treatments at the varices. This article reviews the rationale for the management of patients with cirrhosis and portal hypertension, the current recommendations for the prevention and treatment of variceal bleeding, and outlines the unsolved issues and the perspectives for the future opened by new research developments.

Endoscopic reflectance spectrophotometry and visible light spectroscopy in clinical gastrointestinal studies

The use of reflectance spectrophotometry (RS) for mucosal hemodynamic measurement relies on the recognition of changes in indexes of mucosal hemoglobin concentration and oxygen saturation. Endoscopic application in clinical studies has confirmed important observations demonstrated in animal experiments. The vasoconstriction induced by propranolol, vasopressin, glypressin, or somatostatin in the portal hypertensive gastric mucosa and the reduction of gastroduodenal mucosal perfusion by nonsteroidal anti-inflammatory drugs (NSAIDs) or smoking, mesenteric venoconstriction associated with systemic hypoxia, and acid-induced duodenal hyperemia are important examples. Prognostic predictions include the development of stress-induced gastric ulcerations in patients with significant reductions in gastric perfusion after thermal or head injury, or the demonstration of delayed gastric or duodenal ulcer healing when the hyperemia at the ulcer margin fails to materialize. In mechanical-ventilator-dependent patients with sepsis, a significantly reduced gastric mucosal RS measurement portends a grave prognosis (mortality >80%). Recent advances in technology resulted in the construction and validation of instruments for visible light spectroscopy. Measurements focused on tissue oxygen saturation demonstrated epinephrine and vessel-ligation-induced vasoconstriction, the absence of ischemia in radiation-induced rectal telangiectasias, and gut ischemia responsive to revascularization treatment. Endoscopic RS and visible light spectroscopy are suitable for assessing the role of blood flow in conditions with a lesser degree of ischemia and for testing the hypothesis that functional dyspepsia and dysmotility syndromes may be due to gut ischemia.

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The management of portal hypertension

Portal hypertension is an almost unavoidable complication of cirrhosis, and it is responsible for the more lethal complications of this syndrome. Appearance of these complications represents the major cause of death and liver transplantation in patients who have cirrhosis. This article highlights treatment modalities in use for managing portal hypertension and those that may be available in the future.

Management of gastrointestinal bleeding in patients with cirrhosis of the liver

Ruptured gastroesophageal varices are the most severe and frequent cause of gastrointestinal bleeding in cirrhotic patients, leading to death in 5% to 8% of patients during the first 48 hours. In recent times, the 6-week mortality rate has fallen to 20% due to the development of effective treatment strategies. Initial treatment is aimed at achieving hemostasis and preventing bleeding-related complications such as renal failure, infection, and hepatic decompensation. Blood volume replacement is initiated as soon as possible and antibiotic prophylaxis is instituted from admission. Hemostatic treatment for variceal bleeding includes vasoactive drugs to decrease portal pressure, endoscopic procedures, and portosystemic shunts-either a surgical or transjugular intrahepatic portosystemic shunt (TIPS). Treatment of coagulopathy has only been recently assessed in clinical studies, but results to date are promising. This article reviews the current clinical data on management strategies for variceal bleeding and presents the risks and benefits for each type of treatment. Specific sections on gastric varices and portal hypertensive gastropathy are included.

Diagnosis of portal hypertensive gastropathy

Portal hypertensive gastropathy is a relatively recently described entity that is an important cause of bleeding in portal hypertension. This article focuses on the endoscopic diagnosis of portal hypertensive gastropathy, including a review of different proposed scoring systems, and briefly examines the epidemiology, pathogenesis, and treatment of portal hypertensive gastropathy.

Role of acute elevation of portal venous pressure by exogenous glucagon on gastric mucosal injury in rats with portal hypertension

Time-course studies revealed the increased susceptibility of the gastric mucosa to noxious injury in portal hypertension correlates with the level of elevated portal venous pressure and hyperglucagonemia. Whether acute elevation of portal venous pressure by exogenous glucagon aggravates such injury is not known. We tested the hypothesis that glucagon in a dose sufficient to acutely elevate portal venous pressure aggravates noxious injury of the gastric mucosa in rats with portal hypertension. Infusion of a portal hypotensive dose of somatostatin should reverse these changes. In anesthetized rats with portal vein ligation, glucagon, somatostatin or the combination was administered intravenously in a randomized, coded fashion. Acidified ethanol-induced gastric mucosal injury was determined. Portal venous pressure and gastric mucosal perfusion and oxygenation (reflectance spectrophotometry) were monitored to confirm the effects of the respective intravenous treatments. Exogenous glucagon exacerbated acidified ethanol-induced gastric mucosal injury. The exacerbation was attenuated by somatostatin. These changes paralleled the portal hypertensive and hypotensive effects of glucagon and somatostatin, respectively. Our data suggest that a unique mechanism is triggered with the onset of portal hypertension. In an antagonistic manner, glucagon and somatostatin modulate this novel mechanism that controls portal venous pressure and susceptibility of the gastric mucosa to noxious injury.

Effects of somatostatin and octreotide on portal-systemic collaterals in portal hypertensive rats

BACKGROUND/AIMS

Somatostatin and its long-acting analogue, octreotide, have been used to cease variceal bleeding with uncertain mechanisms. This study investigated whether somatostatin and octreotide have a direct vasoconstrictive effect on the portal-systemic collaterals of portal-hypertensive rats and potentiate the vasoconstriction induced by endothelin-1 in these vascular beds.

METHODS

The vascular responses of collateral vessels to graded concentrations of somatostatin (10(-9)-10(-5) mol/l), octreotide (10(-10)-10(-6) mol/l), norepinephrine (10(-9)-10(-5) mol/l) and vehicle (Krebs solution) were evaluated in perfused collateral vascular beds of rats with portal hypertension induced by partial portal vein ligation. In addition, the perfusion pressure changes of collateral vessels to endothelin-1 (10(-8) mol/l) in the presence of vehicle(control), somatostatin (10(-6) mol/l) and octreotide (10(-6) mol/l) were tested.

RESULTS

Compared with the vehicle group, norepinephrine significantly increased the perfusion pressure of collateral vessels at concentrations between 10(-7) and 10(-5) mol/l. In contrast, neither somatostatin nor octreotide significantly changed the perfusion pressure. Somatostatin and octreotide significantly enhanced the endothelin-1-induced vasoconstrictive effect on the collaterals.

CONCLUSIONS

Somatostatin and octreotide exert no direct vasoconstrictive effect on the collateral vessels of portal hypertensive rats. In the presence of endothelin-1, somatostatin and octreotide exert a local vasoconstrictive effect on these vascular beds.

Gastric varices and portal hypertensive gastropathy

Gastric varices and portal hypertensive gastropathy (PHG) are an important complication of both generalized and segmental portal hypertension. The natural history and risk factors for bleed from GV are not extensively studied as that for esophageal varices. Recently, effective therapy for gastric variceal bleed in form of tissue adhesives, balloon-occluded retrograde transvenous obliteration of gastric varices (BRTO) has been developed. Further advances are still needed regarding natural history, risk factors, bleeding, and mechanism of GV rupture.

Validation of color Doppler EUS for azygos blood flow measurement in patients with cirrhosis: application to the acute hemodynamic effects of somatostatin, octreotide, or placebo

BACKGROUND

Color Doppler EUS (CD-EUS) allows minimally invasive measurement of azygos blood flow (AzBF) in portal hypertension, but further validation of the method is needed. Because a limited number of patients has been studied, the acute hemodynamic effects of somatostatin and octreotide on AzBF and gastric mucosal perfusion are poorly defined in portal hypertension.

METHODS

A double-blind hemodynamic study was designed to assess rapid changes in AzBF over a 60-minute period after intravenous administration of somatostatin, octreotide, and placebo in 30 stable patients with biopsy-proven cirrhosis. AzBF was measured by using both CD-EUS and the invasive thermal dilution technique in the first 10 patients (phase 1). Then, with CD-EUS alone, the hemodynamic study was extended to a further 20 patients (phase 2). In addition, gastric mucosal perfusion changes were assessed by using laser Doppler flowmetry at endoscopy.

RESULTS

In phase 1, the 2 methods for AzBF measurement showed significant correlations both for baseline values (r = 0.685) and for AzBF changes over 60 minutes after drug administration (r = 0.733). In phase 2, a reduction was observed in AzBF 10 minutes after octreotide or somatostatin administration (-47% and -23%, p < 0.0001 vs. placebo, p = 0.058 vs. placebo, respectively). After 60 minutes of somatostatin infusion, AzBF increased 27% over placebo values (p < 0.04). Gastric mucosal perfusion was transiently reduced 5 minutes after octreotide or somatostatin (-21% and -32%, respectively, p < 0.02 vs. placebo).

CONCLUSIONS

This is the first study to validate CD-EUS AzBF measurement with reference to the invasive thermodilution technique in cirrhosis. It confirmed the transient effects of somatostatin and octreotide on both AzBF and gastric mucosal perfusion. In addition, a significant rebound phenomenon after 60 minutes of continuous intravenous somatostatin infusion was observed.

Portal Hypertensive Gastropathy and Gastric Antral Vascular Ectasia

Portal hypertensive gastropathy (PHG) causes both acute and chronic blood loss from the gastrointestinal tract in patients with portal hypertension. Gastric antral vascular ectasia (GAVE) is a distinct condition also associated with portal hypertension that can cause acute and chronic upper gastrointestinal blood loss. These conditions frequently, but not invariably, are diagnosed by upper endoscopy. Although they are fairly prevalent, only 15% to 20% of subjects experience symptomatic gastrointestinal blood loss. Acute gastrointestinal bleeding from PHG should first be treated with octreotide (100 mg bolus intravenously, followed by a 50 mg/h continuous intravenous infusion). If the bleeding does not stop or slow down appreciably within 24 to 48 hours, propranolol may be administered orally to those patients who are hemodynamically stable. Propranolol should be started at 40 mg/d orally in two divided doses. If the patient can tolerate the propranolol and is still bleeding, the dosage may be titrated up to the maximum tolerated amount. For those subjects who are unable to tolerate beta-blockers or continue to bleed despite beta-blocker therapy, transjugular intrahepatic portosystemic shunt (TIPS) is the next line of treatment. Portal decompressive surgery is reserved for those who are not candidates for TIPS and where the appropriate expertise is available. Prevention of chronic gastrointestinal blood loss from PHG should be attempted with beta-blockers, with the dosage titrated up to achieve a resting heart rate of approximately 60 beats per minute. In patients who do not respond to beta-blockers, a TIPS should be placed. The role of long-acting release octreotide in this setting is experimental. The primary treatment of actively bleeding GAVE as well as recurrent bleeding from GAVE is endoscopic ablation of the lesion using either argon plasma coagulation, neodymium:yttrium-aluminum-garnet (Nd:YAG) laser, or heater probe. TIPS and beta-blockers are ineffective for the long-term prevention of recurrent bleeding from GAVE. For selected patients with severe recurrent bleeding or uncontrollable acute bleeding from GAVE, an antrectomy with Billroth I anastomosis may be considered.

Octreotide potentiates PKC-dependent vasoconstrictors in portal-hypertensive and control rats

BACKGROUND & AIMS

The effect of octreotide on vascular tone in the superior mesenteric artery (SMA) was studied in portal-hypertensive (portal vein-ligated) and sham-operated rats.

METHODS

In vitro-perfused SMA vascular beds were tested for the cumulative dose-response to octreotide at baseline conditions and after preconstriction with different vasoconstrictors (alpha1-agonist methoxamine, endothelin [ET-1], phorbol ester [PdBu], and potassium chloride [KCl]).

RESULTS

Octreotide did not affect baseline perfusion pressures (without preconstriction). alpha1-Adrenergic-, ET-1-, and PdBu-, but not KCl-, induced vasoconstriction was significantly potentiated by octreotide. This effect was dose-dependent and not different in portal vein-ligated and sham rats. Amplification of alpha1-adrenergic vasoconstriction by octreotide was significantly enhanced by nitric oxide inhibition (N(W)-nitro-L-arginine, 10(-4) mol/L) as well as by removal of the endothelium, and was completely suppressed by inhibition of protein kinase C (calphostin C, 1 micromol/L), phospholipase A2 (quinacrine, 5 micromol/L), and cyclooxygenase (indomethacin, 20 micromol/L).

CONCLUSIONS

Not directly, but in the presence of vasoconstrictors involving activation of protein kinase C, octreotide exerts a local vasoconstrictive effect on vascular smooth muscle of SMA. This potentiation is equipotent in portal vein-ligated and sham rats, immediate in onset, and mediated via phospholipase A2 and cyclooxygenase-derived prostanoids. This indicates that in preprandial conditions octreotide enhances the vasoconstrictive effect of dependent vasoconstrictors.

Pharmacologic therapy for portal hypertension

Pharmacologic therapy for portal hypertension is effective in the treatment and prevention of hemorrhage from esophagogastric varices. Acute hemorrhage from varices can be treated with intravenous agents such as somatostatin or terlipressin, either alone or in combination with endoscopic sclerotherapy or band ligation. Intravenous octreotide has not shown effectiveness as monotherapy, but it appears to be beneficial when combined with endoscopic treatment. The prevention of rebleeding after initial hemorrhage is best accomplished with non-selective beta blockers, endoscopic band ligation of varices, or a combination of endoscopic and pharmacologic therapies. The addition of oral nitrates may further decrease rebleeding rates, but more data from randomized trials are needed. Beta blockers are currently the only agents recommended for the primary prevention of variceal hemorrhage.

Doppler evaluation of the effects of pharmacological treatment of portal hypertension

The splanchnic pharmacodynamic effects of the drugs used for the treatment of hemorrhagic complications of portal hypertension were poorly clarified until some years ago. The introduction of Doppler ultrasound provided a powerful tool to investigate such hemodynamic effects and brought new insights in this field. The present article reviews the pharmacodynamics of the substances used in the treatment of portal hypertension, with particular regard to the effects assessable by duplex Doppler ultrasonography.

Underlying mechanisms of portal hypertensive gastropathy

Gastric mucosal lesions are frequently observed in patients with liver cirrhosis and portal hypertension. Similar lesions can be observed in experimental portal hypertension. This review summarizes our current knowledge of the pathophysiology of portal hypertensive gastropathy, with a particular focus on the microcirculatory disturbances that characterize this condition. The stomach of cirrhotic patients exhibits an increased susceptibility to injury induced by several irritants. Similarly, the stomach of portal hypertensive animals is less resistant to injury. One of the most important factors contributing to the increased susceptibility to damage is an impaired hyperemic response when the epithelium is exposed to irritants. This appears to be related to a reduction in mucosal prostaglandin production and to altered microcirculatory responsiveness to nitric oxide. Nitric oxide overproduction in portal hypertension may have direct effects on gastric blood flow regulation. Elevated production of tumor necrosis factor-alpha by gastric mucosa in portal hypertensive rats has also been shown to contribute to mucosal injury. A better understanding of the pathogenesis of portal hypertensive gastropathy may lead to development of specific therapeutic interventions for this condition.

Portal hypertensive gastropathy in noncirrhotic patients. The effect of lienorenal shunts

We studied 25 consecutive patients with noncirrhotic portal hypertension to determine whether portal hypertensive gastropathy occurred and whether it was related to hypoacidity, hypergastrinemia, or portal venous congestion. Preoperative tests included gastrointestinal endoscopy, gastric mucosal biopsies, gastric acid estimation, and serum gastrin measurements. All patients had a central splenorenal shunt performed during which a full-thickness gastric biopsy was performed. The tests were repeated 3 to 16 months postoperatively. Eight of the 25 patients showed endoscopic evidence of portal hypertensive gastropathy. The shunt procedure reversed the gastropathy in 6 of 7 patients followed up. Mucosal biopsies revealed vascular ectasia in 24 of 25 patients; in 8 of the most severely affected there was partial or complete regression after surgery. The basal and peak acid outputs in the patients were normal for our laboratory at 2.9 +/- 0.25 meq/hour and 16.37 +/- 0.96 meq/hour, respectively. They remained unchanged after surgery. Fasting serum gastrin levels were also normal both before and after surgery. Our findings indicate that venous congestion is the cause of portal hypertensive gastropathy in patients with noncirrhotic portal hypertension and that it can be reversed by a decompressive procedure.

Early administration of somatostatin and efficacy of sclerotherapy in acute oesophageal variceal bleeds: the European Acute Bleeding Oesophageal Variceal Episodes (ABOVE) randomised trial

BACKGROUND

Sclerotherapy is widely used for acute variceal bleeding, although in emergencies bleeding makes it difficult to obtain the clear view required for safe and effective treatment. We investigated whether early administration of somatostatin would improve the efficacy of sclerotherapy.

METHODS

In this double-blind, prospective trial, patients who had cirrhosis with upper-gastrointestinal bleeding were randomly assigned natural somatostatin (6 mg per 24 h) or placebo for 120 h. In addition, intravenous bolus doses of somatostatin (250 micrograms) or placebo were injected after the start of the infusion, before emergency endoscopy or sclerotherapy, and when active bleeding was observed. The primary endpoint was treatment failure, defined as the occurrence during the infusion period of at least one of: excess transfusion of blood products, haematemesis, haemodynamic instability, need for rescue therapy, or death.

FINDINGS

205 patients were enrolled: 101 received somatostatin and 104 received placebo. Treatment failed in 35 somatostatin and 57 placebo recipients (p = 0.004); death or use of rescue therapy occurred in nine and 19 patients, respectively (p = 0.05). The mean quantity of blood products transfused over 120 h (adjusted for baseline haemoglobin) was 2.64 (SD 0.35) units in the somatostatin group versus 3.62 (0.35) units in the placebo group (p = 0.05). At endoscopy, active bleeding from oesophageal varices was less frequent (27 vs 42 patients, p = 0.012) and the sclerotherapy procedure was easier (2.8 vs 4.7 cm, p = 0.0027) in the somatostatin than in the placebo group.

INTERPRETATION

Early administration of natural somatostatin continued for 120 h, combined with additional bolus injections, is more effective than placebo in the overall control of acute variceal haemorrhage in patients with cirrhosis undergoing sclerotherapy.

Portal Hypertensive gastropathy

The term portal hypertensive gastropathy (PHG) defines a wide spectrum of diffuse macroscopic lesions that appear in the gastric mucosa of patients with portal hypertension. Histologically, these lesions correspond to dilated vessels in the mucosa and submucosa in the absence of erosions or inflammation. Endoscopically, the lesions are classified as mild when mosaic pattern or superficial reddening are present, and severe when gastric mucosa appear with diffuse cherry red spots. Mild lesions are highly prevalent (65-90%), whereas severe lesions are present in only 10-25% of cirrhotic patients. The pathogenesis of PHG is not well known, but both venous congestion related with raised portal pressure and increased gastric blood flow seem to be crucial factors for its development. Variceal sclerosis may contribute to the development or aggravation of the lesions. Bleeding is the unique clinical manifestation of PHG, and occurs only in those patients with severe lesions. During a 5-year follow-up, the risk of overt bleeding or chronic bleeding, which induces anaemia, is 60 % and 90%, respectively, for patients with severe PHG. Propranolol is the only pharmacological treatment that has been proven useful in preventing bleeding from PHG. Porto-systemic shunts and liver transplantation are also effective.

Somatostatin reduces gastric mucosal blood flow in patients with portal hypertensive gastropathy: a randomized, double-blind crossover study

Agents which decrease gastric mucosal blood flow (GMBF) are postulated to have beneficial effects in arresting gastrointestinal bleeding in cirrhotic patients with portal hypertension. Our objective was to test the hypothesis that in a dose that significantly lowers wedged hepatic venous pressure (WHVP), a bolus injection of somatostatin will significantly decrease GMBF in patients with portal hypertensive gastropathy (PHG). In this placebo-controlled, double-blind, crossover study, 20 cirrhotic patients with PHG were randomly assigned to receive either somatostatin followed by placebo (Group A) or placebo followed by somatostatin (Group B). Wedged hepatic venous pressure was monitored. GMBF in the antrum and corpus was assessed by reflectance spectrophotometry. Indices of hemoglobin concentration (IHb) and indices of oxygen content (ISO2) were recorded. Nine patients were assigned to Group A, and 11 to Group B. Mild PHG was seen in 16 patients, and severe PHG in 4 patients. Baseline WHVP, IHb, and ISO2 were similar in both treatment groups. Wedged hepatic venous pressure (WHVP) was significantly lowered [median, 17.6%; interquartile range (-27.0,-12.6%); P = 0.0008] after a 250-microg bolus injection of somatostatin. This dose of somatostatin significantly reduced IHb both in the antrum [-10.2% (-23.4, 0.4%)] and in the corpus [-5.8% (-16.6, 5.6%)] compared to placebo (P = 0.02 and 0.04, respectively). Intravenous bolus injection of 250 microg somatostatin significantly reduces WHVP and GMBF in patients with PHG. Whether this ability to decrease the GMBF in PHG makes somatostatin an effective treatment in acute gastrointestinal bleeding in PHG deserves to be studied.

Management of upper gastrointestinal bleeding in the patient with chronic liver disease

This article reviews the management of severe upper gastrointestinal bleeding in the patient with chronic liver diseases. The initial assessment, diagnostic work-up, and treatment options for variceal and nonvariceal bleeding are discussed. The role of diagnostic and therapeutic endoscopy for esophagogastric varices is reviewed with special emphasis on new endoscopic techniques including variceal band ligation and cyanoacrylate injection. Various pharmacologic, surgical, and radiologic treatment options for variceal bleeding also are discussed. In addition, nonvariceal causes of severe upper gastrointestinal bleeding are reviewed including peptic ulcer diseases, Mallory-Weiss tear, portal hypertensive gastropathy, and gastric antral vascular ectasia.

Somatostatin attenuates the hyperdynamic circulatory state in the gastric mucosa of rats with portal hypertension

BACKGROUND

Portal hypertensive gastropathy is characterized by a hyperdynamic circulatory state in the gastric mucosa. We assessed the effect of bolus injection of somatostatin on gastric mucosal perfusion in a rat model of portal hypertension. We tested the hypothesis that somatostatin will reduce gastric mucosal perfusion in portal hypertension.

METHODS

Portal hypertension was induced by two-stage portal vein ligation (PVL). Two weeks after PVL significant elevation of portal venous pressure was demonstrated. Gastric mucosal hemodynamic changes were measured by reflectance spectrophotometry, which records the indexes of mucosal hemoglobin oxygen saturation (ISO2) and mucosal hemoglobin concentration (IHB).

RESULTS

After an intravenous bolus of 1 microgram somatostatin significant reductions of ISO2 and IHB were demonstrated in the rats with PVL (ISO2, -34 +/- 5%; IHB, -15 +/- 2%) and the controls (ISO2, -26 +/- 4%; IHB, -15 +/- 2%). A dose-response relationship was shown by using 0.01, 0.1, and 1 microgram of somatostatin. Somatostatin did not induce other hemodynamic changes except a transient drop in systemic blood pressure of 8-10%.

CONCLUSION

The significant reductions of gastric mucosal ISO2 and IHB by somatostatin support the hypothesis that somatostatin is capable of attenuating the hyperdynamic circulatory state in the gastric mucosa of rats with portal hypertension and may have a beneficial effect on portal hypertensive gastropathy. This hypothesis deserves to be evaluated in clinical studies.