Eighty male Wistar rats, 170 to 190 g, were randomly divided into two groups: a model group (60 rats) and a control group (20 rats). The model group was given alcoholic intragastric administration plus an
olive oil diet. Gavage, twice a day, was used to administer
ethanol (30%) in a dose of 4 g/kg/d to the model group rats in the first 4 weeks. In the next 4 weeks, 40%
ethanol in a dose of 5 g/kg/d was used, and then in the last 4 weeks, 50%
ethanol in a dose of 6 g/kg/d was used. After infusion for 12 weeks, 15 rats (
fatty liver group) were sacrificed. Others were divided into two groups; one was the
hepatitis group with continued alcohol intragastric administration, the other was the
hepatitis control group, receiving equal amounts of
normal saline. Both groups were sacrificed after 4 weeks. By HE staining, histological pathology of the rat livers was analyzed. The expression of
proteasome LMP7 subunit
mRNA was examined by reverse transcription and real-time PCR. The content of LMP7
subunit protein was determined by Western blot.
RESULTS: The LMP7
mRNA level of the
fatty liver group was 36% of the control group. The level of the
hepatitis control group was 51% of the control group. The level of the
hepatitis group was the lowest, which was only 26% of the control group. Western blot results showed that the level of the
LMP7 protein content of the control group was 0.50+/-0.01; the level was 0.39+/-0.02 of the
fatty liver group; 0.30+/-0.04 of the
hepatitis group, and 0.38+/-0.02 of the
hepatitis control group. The differences of the
LMP7 protein content and
mRNA expression correlated with the severity of the pathological alterations of the livers.
CONCLUSIONS: