Study of canine intrahepatic portal hypertension model induced by intra-portal injection of Sephadex microspheres

【Objective】 Establishment of canine portal hypertension model by intra-portal injection of Sephadex microspheres,observe the hemodynamics changes by ALC-Ultrasonic Blood Flow System,and study the mechanism of portal hypertension.【Methods】 Sixteen mongrel dogs were randomly divided into control group(n = 6) and experimental group(n =10) after portal catheterization;the experimental group were given an injection of Sephadex through the catheter once every five days,six times in total;the control group received saline in the same way.Portal venous pressure measurement,blood cell counting,liver function test,portography,liver histological examinations were performed;Observe the hemodynamic changes of portal vein,splenic vein,hepatic artery and splenic artery by ALC-Ultrasonic Blood Flow System.【Results】 The Portal venous pressure increased immediately after the injection of Sephadex microspheres,which was(23.35 ± 2.63) cm H2O on 4 months after operation;In the experimental group of 4 months after operation,the histological examination showed significant fibrosis in the portal area of the liver,Portography showed profuse portosystemic collateral circulations.The size of portal vein,splenic vein,splenic artery and hepatic artery of the experimental group were dilatated.The maximum speed of blood flow in portal vein and splenic vein decreased significantly;the average volume of blood flow changed slightly in the portal vein but increased significantly in splenic vein;both the maximum speed of blood flow and average volume of blood flow in the hepatic artery and splenic artery increased significantly.【Conclusion】Intraportal injection of Sephadex could induce stable intrahepatic portal hypertension model.The blood flow of portal system became slower and as a compensatory result,the volume of blood flow in the hepatic artery and splenic artery increased.