Research on the establishment a model of prehepatic portal hypertension in dogs

Objective To establish a new model with partial portal vein ligation at first and additional splenic vein stenosis and its collateral branches thoroughly ligated three weeks later,to observe change of the portal venous system in order to make sure whether it could establish a model of portal hypertension with hypersplenism or not.Methods Twenty-five dogs were divided into three groups: group A(normal group,n=5),group B(control group,n=10) and group C(experimental group,n=10).Partial portal vein ligation was proceeded in group B,in group C the model was establised by partial portal vein ligation at first and additional splenic vein stenosis combined with its collateral branches thoroughly ligated three weeks later,dogs in group A were just undergone lapboratory incision.Portal vein pressure,size of spleen the collateral circulation of portal vein and the fluctuation of hematocyte counts were measured and recorded at the preconcerted time.Histopathological changes of spleen and condition of bone marrow hyperplasia were examined.Results Two kinds of method of prehepatic portal hypertension developed in group B and C,the portal vein pressure increased significantly after nine weeks operating in both group B and group C.The RBC and PLT counts in group C decreased obviously compared to group A and B after nine weeks operating.The splenic histopathology changes conformed to the changes of the congestive splenomegaly,and the hyperplasia of bone marrow was much more a obvious.Conclusion This new method of establishing a model of portal hypertension is proved to be feasible,especially it can form satisfactory hypersplenism,so that it may be useful in the scientific research.