Common bile duct ligation in the rat: a model of intrapulmonary
vasodilatation and the hepatopulmonary syndrome.
Fallon, Michael B., Gary A. Abrams, John W. McGrath, Zihying Hou, and
Bao Luo.
Department of Internal Medicine and Liver Center, The University of
Alabama at Birmingham, Birmingham, Alabama
APStracts 3:0243G, 1996.
Hepatopulmonary syndrome (HPS) causes impaired oxygenation due to
intrapulmonary vasodilatation in patients with cirrhosis. Chronic
common bile duct ligation (CBDL) in the rat results in gas exchange
abnormalities similar to HPS, but intrapulmonary vasodilatation has
not been evaluated. We assess intrapulmonary vasodilatation, measured
in vivo, after CBDL. Sham, 2 and 5 week CBDL and 3 week partial
portal vein ligated (PVL) rats had hepatic and lung injury, portal
pressure and arterial blood gases assessed. The pulmonary
microcirculation was evaluated by injecting microspheres (size range
5.5 - 10 um) intravenously and measuring the size and number of
microspheres bypassing the lungs in arterial blood. CBDL animals
developed progressive hepatic injury and portal hypertension
accompanied by gas exchange abnormalities and intrapulmonary
vasodilatation. PVL animals, with a similar degree of portal
hypertension, did not develop intrapulmonary vasodilatation or
abnormal gas exchange. No lung injury was observed. CBDL, but not
PVL, causes progressive intrapulmonary vasodilatation, which
accompanies worsening arterial gas exchange. These findings validate
CBDL as a model to study HPS.
Received 23 May 1996; accepted in final form 31 October 1996.
APS Manuscript Number G207-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996