Bone disorders in experimentally induced liver disease in growing rats

To investigate the change of bone parameters in a new model of experimentally induced liver cirrhosis and hepatocellular carcinoma (HCC) in growing rats.

Fischer-344 rats (n = 55) were used. Carbon tetrachloride (CCl(4)), phenobarbital (PB), and a single diethylnitrosamine (DEN) injection were used. Animals were killed at wk 8 and 16. Bone mineral content, femoral length, cortical index (quotient of cortical thickness and whole diameter) and ultimate bending load (F(max)) of the femora were determined. The results in animals treated with DEN+PB+CCl(4) (DPC, n = 21) were compared to those in untreated animals (UNT, n = 14) and in control group treated only with DEN+PB (DP, n = 20).

Fatty liver and cirrhosis developed in each DPC-treated rat at wk 8 and HCC was presented at wk 16. No skeletal changes were found in this group at wk 8, but each parameter was lower (P<0.05 for each) at wk 16 in comparison to the control group. Neither fatty liver nor cirrhosis was observed in DP-treated animals at any time point. Femoral length and F(max) values were higher (P<0.05 for both) in DP-treated animals at wk 8 compared to the UNT controls. However, no difference was found at wk 16.

Experimental liver cirrhosis and HCC are accompanied with inhibited skeletal growth, reduced bone mass, and decreased mechanical resistance in growing rats. Our results are in concordance with the data of other studies using different animal models. A novel finding is the transiently accelerated skeletal growth and bone strength after a 8-wk long phenobarbital treatment following diethylnitrosamine injection.