title: The subcutaneous splenic transposition prevents liver injury induced by excessive portal pressure after massive hepatectomy.
abstract: OBJECTIVE
  We have proposed that acute portal hypertension, reflecting sinusoidal shear stress, becomes a trigger of liver regeneration after partial hepatectomy. Moreover, excessive shear stress induces liver injury. We investigated whether the use of a portosystemic shunt can reduce surplus damage of the remnant liver by means of excessive shear stress after massive hepatectomy.
  
  
  METHODS
  In this study, to determine whether and by what mechanism excessive shear stress induces liver injury, we used the rat model to investigate whether a subcutaneous splenic transposition, which consists of a portosystemic shunt up to 4 weeks post-surgery, can prevent liver injury.
  
  
  RESULTS
  Subcutaneous splenic transposition decreased the portal pressure immediately after 90% massive hepatectomy and relieved the elevation of transaminase and serum hyaluronic acid compared with findings of the no shunt group. In addition, the degree of leukocytopenia and thrombocytopenia in 90% massive hepatectomy with subcutaneous splenic transposition were better than those in 90% massive hepatectomy without subcutaneous splenic transposition. Serum tumor necrosis factor-alpha levels of the shunt group were lower than those of massive hepatectomy without subcutaneous splenic transposition. The rats that underwent 95% massive hepatectomy died within 48 hrs. The extent to which subcutaneous splenic transposition prolonged survival after 95% massive hepatectomy was statistically significant (mean survival of shunt group 60.9 +/- 13.4 hours vs. no shunt group 25.4 +/- 2.3 hours P = 0.001).
  
  
  CONCLUSIONS
  These findings suggest that excessive shear stress after massive hepatectomy induces the liver injury against the hepatocytes and the sinusodial endothelial cells via intrahepatic microcirculation failure accompanied by overimmunoreaction.
authors.affiliation: First Department of Surgery, School of Medicine, Niigata University, Niigata, Japan.
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Koyama
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Sato
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Hatakeyama
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006498:Hepatectomy / Q000009:adverse effects*; D006975:Hypertension, Portal / Q000209:etiology* / Q000503:physiopathology / Q000601:surgery*; D008099:Liver / Q000293:injuries* / Q000503:physiopathology / Q000601:surgery*; D008107:Liver Diseases / Q000209:etiology* / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D011170:Portasystemic Shunt, Surgical; D051381:Rats; D011917:Rats, Inbred Lew; D033081:Shear Strength; D013154:Spleen / Q000503:physiopathology / Q000601:surgery*; D015996:Survival Rate