Effects Of Shear Stress On The Secretion Function Of Rat Liver Sinusoidal Endothelial Cells

What triggers the initiation of liver regeneration after partial hepatectomy(PHx) is still unknown although we all know liver can regenerate in such situation. Liver regeneration is a complicated process in which hepatocytes and nonparenchymal cells as well as many cytokines are involved. Earlier studies had shown that when hepatic tissue or isolated hepatocytes are transplanted into extrahepatic sites, they also enter into DNA synthesis after PHx of the host. That suggests there must be some mitogen in blood which have propelled hepatocytes to regenerate. Hepatocyte growth factor(HGF) is the first blood-derived mitogen being identified as initiator for proliferation of hepatocyte and the main factor to drive cell cycle from stage G1 to S. HGF is secreted by nonparenchymal cell, such as liver sinusoidal endothelial cell, fat-storing cell and Kuffer cell and can stimulate regeneration of hepatocyte through paracrine and autocrine pathway. HGF has also been found having the effect of keeping stability of hepatocyte membrane. In normal HGF stay inactive in blood and can be activated by enzymes to initiate proliferation of hepatocytes.Interleukin-6( IL-6), a cytokine produced by liver and intestine cell, has been identified to be indispensable to liver regeneration. When transfected with human IL-6 gene, hepatocytes of Chinese hamster proliferate spreadly and result in increase of liver volume, which suggests that IL-6 may act as mitogen after PHx to trigger hepatocyte regeneration. In several experiments researchers find that in mice lacking IL-6 regeneration capacity of liver can be impaired and damage to hepatocyte also increase after PHx, but it can be ameliorated if IL-6 is administrated before PHx. IL-6 can induce STAT3 into hepatocyte nucleus directly to make early gene activated and initiate mitosis. TNF-α,EGF,TGF-αare aslo blood-derived mitogen for hepatocyte besides IL-6. Egucbi found in the first 3 months after partial living donor liver transplantation(LDLT),mean portal venous (PV) velocity was greater in the liver cirrhosis(LC) group than the fulminant hepatic failure(FHF) group. Liver regeneration also was more rapid in the LC group than the FHF group and reached 100% standard liver volume(SLV) as early as 2 weeks posttransplantation ,whereas the FHF group reached...