title: Altered intrahepatic microcirculation of idiopathic portal hypertension in relation to glutamine synthetase expression.
abstract: OBJECTIVE
  Alteration in intrahepatic microcirculation of idiopathic portal hypertension (IPH) has been poorly understood. This study aimed to characterize altered intrahepatic microcirculation of IPH focusing on the expression pattern of glutamine synthetase (GS).
  
  
  METHODS
  Immunohistochemical staining of GS was performed using liver sections of IPH (n = 28). Serial section analysis was performed to determine microcirculatory disturbances of IPH.
  
  
  RESULTS
  Paraportal shunt vessels were observed in 20 cases of IPH, and they were divided into two types according to the GS staining pattern; hepatocytes surrounding the vessels were negative for GS (type 1) and positive for GS (type 2). All 20 cases had one or more type 1 vessels within a section, and 10 cases were further associated with type 2 vessels. The cases with type 2 vessels showed infrequent symptoms of esophageal varices. Regarding the GS staining as an indicator of hepatic veins, some type 2 vessels were supposed to represent portovenous shunts. Isolated arteries in hepatic parenchyma were present in 21 cases, and they were located around terminal hepatic venules in six cases, corresponding to centrizonal arteries. Broad hepatocellular GS staining in hyperplastic lesions was noted in five cases, whereas nodular regenerative hyperplasia lacked GS expression.
  
  
  CONCLUSIONS
  GS immunostaining revealed microcirculatory disturbances of IPH that were associated with abnormalities in both venous and arterial vessels.
authors.affiliation: Department of Human Pathology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Department of Human Pathology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Harada
authors.affiliation: Department of Human Pathology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
authors.forename: Motoko
authors.initials: M
authors.lastname: Sasaki
authors.affiliation: Department of Human Pathology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.|Department of Pathology, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Yasuni
authors.initials: Y
authors.lastname: Nakanuma
keywords: glutamine synthetase; idiopathic portal hypertension; isolated artery; microcirculation; paraportal shunt vessel