Establishment of alcohol-induced liver injury model in rats

Objective: To establish alcohol-induced liver injury model in rats and lay foundation for further study on mechanism of drug protecting alcoholic liver injury.Methods: Seventy Sprague-Dawley rats were randomly divided into one control group and four model groups.Model groups were given 45% diluted alcohol 10 mL/kg per day by gavage for 1(model group 1),2(model group 2),4(model group 3),and 8 weeks(model group 4),respectively.The control group was given distilled water by gavage for 3 days.Rats were sacrificed,livers extracted for pathological observation.The activity of alanine transarninase(ALT),aspartate transarninase(AST),triglyceride(TG) in serum and the activity or content of superoxide dismutase(SOD) and malondialdehyde(MDA) in liver were measured.Results: Compared with the control group,the serum ALT,AST and TG were not significantly changed in the model group 1 and 2,but the serum ALT was significant higher in model group 2 than that in the control group(89.73±15.06 vs.78.59±11.62,P0.05).The serum AST and TG were increased(166.49±15.73 vs.154.07±9.38;0.93±0.21 vs.0.71±0.19,P all 0.05) ALT activity also significantly inreased(112.36±9.84 vs.78.59±11.62) in model group 4.Compared with the control group,the activity of SOD and the content of MDA were not significantly changed in model group 1 and 2;but the activity of SOD in model group 3 was significantly decreased(98.41 ±12.60 vs.127.52±13.09,P0.01),content of MDA was increased(6.05±1.47 vs.4.62±1.24,P0.05).The activity of SOD was decreased(109.76±23.05 vs.127.52±13.09,P0.05),but the content of MDA was not changed in model group 4.Under microscope,obvious fatty degeneration was observed in model group 3 and typical alcoholic liver fibrosis was obvious in model group 4.Conclusion: The alcoholic liver injury of different stages were induced by 45% diluted alcohol by gavage,which could be applied in study of mechanism of drug protecting alcoholic liver injury in rats.