The evolution of changes in quantitative liver function tests in a rat model of biliary cirrhosis: correlation with morphometric measurement of hepatocyte mass.

The aim of this study was to determine the prognostic significance of functional changes in the liver during progression of cirrhosis. Liver function was quantitated weekly by the aminopyrine breath test (measuring microsomal function) and the galactose breath test (measuring cytosolic function) in rats made cirrhotic by bile duct ligation (n = 14) and in sham-surgery controls (n = 9). Nine rats died spontaneously of cirrhosis. Both the aminopyrine breath test and galactose breath test were sensitive (89%) predictors of death within 1 week, but the galactose breath test was more specific (83%). Morphometric measurements of livers from surviving cirrhotic animals and controls (n = 5 each) showed that mean hepatocyte mass was maintained in the cirrhotic livers [cirrhosis (17.0 +/- 2.0) vs. controls (13.9 +/- 0.9 gm)]. The galactose breath test was also maintained, whereas the aminopyrine breath test was significantly decreased in the surviving cirrhotics. The galactose breath test, but not the aminopyrine breath test, correlated with hepatocyte mass (r = 0.67). The aminopyrine breath test correlated with microsomal aminopyrine N-demethylase activity (r = 0.78). Serial use of quantitative liver tests allows prediction of time of death from cirrhosis in this model.