[Experimental observation of high portal venous resistance in dogs]

To study the relationship between portal resistance and formation of portal hypertension, we designed a high portal systemic resistance model by injecting bletilla hyacinthina into the intrahepatic portal venulae through the portal vein in 9 dogs. The portal pressure was measured and the portal hemodynamics studied by ultrasonic Doppler before operation, and the data were collected with re-laparotomy after 10, 20 days respectively. Liver function, portal collateral circulation and liver histology were also observed. Our results suggest that the portal high resistance could cause portal hypertension. The elevation of FPP was maintained and portal blood flow was increased constantly in different degrees. The veins of the abdominal wall and esophagus were dilated slightly. Histological study of the liver showed fibrotic hyperplasia in the portal area. Liver function was not markedly changed except elevation of ALP. It seems that the combination of portal resistance and portal hyperdynamics are the necessary pathogenic factor of formation of portal hypertension.