Tetrahydrobiopterin (BH4) is an essential cofactor in NO synthesis by endothelial nitric oxide synthase (eNOS) enzymes. It has been previously suggested that reduced intrahepatic BH4 results in a decrease in intrahepatic NO and contributes to increased hepatic vascular resistance and portal pressure in animal models of cirrhosis. The main aim of the present study was to evaluate the relationship between BH4 and portal hypertension (PHT). One hundred ninety-three consecutive patients with chronic liver disease were included in the study. Liver biopsy, measurement of BH4 and hepatic venous pressure gradient (HVPG) were performed. Hepatic fibrosis was classified using the Laennec fibrosis scoring system. BH4 levels were determined in homogenized liver tissues of patients using a high performance liquid chromatography (HPLC) system. Statistical analysis was performed to evaluate the relationship between BH4 and HVPG, grade of hepatic fibrosis, clinical stage of cirrhosis, Child-Pugh class. A positive relationship between HVPG and hepatic fibrosis grade, clinical stage of cirrhosis and Child-Pugh class was observed. However, the BH4 level showed no significant correlation with HVPG or clinical features of cirrhosis. BH4 concentration in liver tissue has little relation to the severity of portal hypertension in patients with chronic liver disease.
Adult ; Aged ; Biopterin/*analogs & derivatives/analysis ; *Chromatography, High Pressure Liquid ; Chronic Disease ; Elasticity Imaging Techniques ; Female ; Hepatic Veins/physiology ; Humans ; Hypertension, Portal/complications/*diagnosis/metabolism ; Liver/pathology ; Liver Cirrhosis/ultrasonography ; Liver Diseases/complications/*diagnosis/metabolism ; Male ; Middle Aged ; Nitric Oxide/metabolism ; Portal Pressure ; Regression Analysis ; Severity of Illness Index

Animals ; Antihypertensive Agents ; therapeutic use ; Esophageal and Gastric Varices ; complications ; prevention & control ; Gastroscopy ; Hepatic Stellate Cells ; metabolism ; Humans ; Hypertension, Portal ; diagnosis ; etiology ; therapy ; Liver Cirrhosis ; complications ; Portasystemic Shunt, Transjugular Intrahepatic

Portal hypertensive gastropathy (PHG) is a term used to define the endoscopic findings of gastric mucosa with a characteristic mosaic-like pattern with or without red spots, and a common finding in patients with portal hypertension. These endoscopic findings correspond to dilated mucosal capillaries without inflammation. The pathogenesis of PHG in not well known, but portal hypertension and some humoral factors seem to be crucial factors for its development. Pharmacological (e.g. propranolol), or interventional radiological (such as transjugular intrahepatic portosystemic shunt) procedures may be useful in preventing re-bleeding from PHG. The classic features of gastric antral vascular ectasia (GAVE) syndrome include red, often haemorrhagic lesions predominantly located in the gastric antrum which can result in significant blood loss. Although the pathogenesis of GAVE is not clearly defined, it seems to be a separate disease entity from PHG, because GAVE generally does not respond to a reduction of portal pressures. Endoscopic ablation (such as argon plasma coagulation) is the first-line treatment of choice. This review will focus on the incidence, clinical importance, etiology, pathophysiology, and treatment of PHG and GAVE syndrome in the setting of portal hypertension.
Esophageal and Gastric Varices/*diagnosis/etiology/therapy ; Gastric Antral Vascular Ectasia/*diagnosis/etiology/therapy ; Gastric Mucosa/metabolism/pathology ; Humans ; Hypertension, Portal/*complications ; Portasystemic Shunt, Transjugular Intrahepatic ; Vasodilator Agents/therapeutic use