Effects of Early Cirrhosis on Hepatic Vascular Resistance in the Rat
AbstractThe Problem. Increased vascular resistance in the liver is a common symptom of established cirrhosis of the liver. This investigation measured changes in resistance during induction of cirrhosis, to determine whether the
increase in vascular resistance might be part of the mechanism by which cirrhosis develops.
Procedure. Early cirrhosis was induced in rats by injections of a C Cl4 and olive oil over a 35 day period. The livers were excised and perfused with aerated Locke's solution through the hepatic portal vein, using 13 different flow rates. Portal pressures at these flow rates were recorded continuously. Resistances were calculated as the ratio of pressure to flow rate, for each of three groups of livers: those from uninjected control rats, those from rats injected with olive oil, and those from rats injected with olive oil and C Cl4.
Findings. Resistance was found to be significantly higher in livers of rats injected with olive oil or with olive oil plus C Cl4, than in livers of uninjected control rats. The difference was especially noticeable at the lower flow rates.
Conclusions. It is clear that increased vascular resistance is not merely a late side-effect of cirrhosis.
Recommendations. More detailed studies should be made to describe the changes in resistance during induction of cirrhosis, and to establish the structural basis of this increased resistance