Abstract: Objective To investigate whether transforming growth factor-beta 1(TGF-β1) is involved in the process of carbon tetrachloride(CCl₄)-induced acute chemical liver injury.Methods Acute liver injury in mouse was induced by intraperitoneal injection of CCl₄.The level of serum TGF-β1 in mouse was detected with enzyme-linkde immunosorbent assay(ELISA).The expression of TGF-β1 signaling molecules Smad2,3 mRNA was examined with reverse transcriptase PCR(RT-PCR).Results Both levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST)and TGF-β1 in serum of mouse increased significantly at 1st and 3rd date after CCl₄ treatment (P < 0.01 for all).RT-PCR results showed that the expression of TGF-β1 mRNA in liver was up-regulated significantly in CCl₄-treated mouse compared with that in the control mouse treated with olive oil,and the expressions of TβRII,signaling molecules Smad2,3 mRNA were also obviously up-regulated.Conclusion Levels of TGF-β1 and signaling molecules Smad2,Smad3 increase during CCl₄-induced acute chemical liver injury in mouse,which suggest that TGF-β1 is involved in the process of CCl₄-induced acute chemical liver injury.