Objective    To establish an animal model of hepatic inflow occlusion with meso-caval shunt in Bama swines and to evaluate the tolerance limit of portal vein occlusion.     Methods    Fourteen Bama swines were divided into group A and group B

and their portal vein blood inflow was blocked respectively for 120

1

50 min. The animal survival rate

the changes of liver function and histopathology were observed before occlusion and reflow

and 2 h

1

3

5 d after reflow.     Results    All through the portal vein occlusion process

the gut was of no significant congestion and in normal color

suggesting the temporary portacaval shunt is efficient. The animal survival rate of group A was significantly higher than that of group B (100%

vs

57.1%

P<

0.05). For groups A and B

a rise of their ALT

AST

TBIL values were observed

and those changes in group B were higher than those of group A. At 150 min after portal vein occlusion

great amount of hemorrhage

WBC aggregation

cell vacuolation and focal necrosis of hepatic tissues in portal area were observed in group B. Two hours after reflow

further deteriorated lesions occurred

such as fat degeneration

ballooning degeneration of hepatocyte

swelling endothelial cells

   and congestion of sinus hepaticus under light microscope or electron microscope

less severe in group A than group B. Under electron microscope

mitochondrial edema and the expansion of endoplasmic reticulum of group B were more obvious

and additionally there were most concentrated nucleus

deposition of fibrous matrix

and other  irreversible injury.     Conclusion    Two hours is the tolerance limit for the portal vein occlusion for Bama swine under the condition of meso-caval shunt.