Abstract: BACKGROUND ＆ AIM:To search for the differentially expressed genes related to lipid metabolism in the liver of Balb/c mouse treated by tetracycline hydrochloride using mouse toxicological microarray. MATERIAL AND METHODS: The mouse toxicological microarray was developed. The model of tetracycline hydrochloride damaging mouse liver ,which included two doses (200 mg/(kg·d) and 50 mg/(kg·d))and three time phases,was established.The total RNA of mouse liver was isolated for hybridization experiment of the microarray. RESULTS: 28 genes differentially expressed in all treated groups were found. These were involved in lipid synthesis，catabolisim and transport in the liver,preliminary analyses of these gene functions and their relationship were performed. CONCLUSION： Multiple genes were markedly changed in the liver of Balb/c mouse treated by tetracycline hydrochloride.This set the stage for further research on the molecular mechanisms of the hepatoxicity of tetracycline.

Key words: gene chip, tetracycline, liver