Article

Morphological and biomechanical remodelling of the hepatic artery in a swine model of portal hypertension.

Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, China.
Hepatology International (Impact Factor: 2.64). 09/2011; DOI: 10.1007/s12072-011-9302-y
Source: PubMed

ABSTRACT OBJECTIVES: To obtain the biomechanical and morphological remodelling of hepatic arteries in swine with portal hypertension. METHODS: A number of 20 white pigs was used, of which 14 were subjected to liver cirrhosis and portal hypertension (PHT) induced by carbon tetrachloride and pentobarbital; the rest were used as the control group. The biomechanical remodelling of the hepatic arteries was measured, namely, the incremental elastic modulus (E (inc)), pressure-strain elastic modulus (E (p)), volume elastic modulus (E (v)), the incremental compliance (C), the opening angle and the stained microstructural components of the vessels. RESULTS: The percentages for the microstructural components and the histologic data significantly changed in the experimental group, three incremental elastic moduli (E (inc), E (p), and E (v)) of the experimental group were significantly larger than those of the control group (P < 0.05); the compliance of hepatic arteries decreased greatly (P < 0.05) too. The opening angle (OA) was considerably larger than that of control group (P < 0.05). CONCLUSIONS: The study suggests that the morphological and biomechanical properties of swine hepatic arteries have changed significantly during the process of portal hypertension and that from biomechanical aspects, the hepatic arteries have also suffered from extensive remodelling, which in turn deteriorates the existing portal hypertension.

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