Abstract： Objective To observe the effect of high glucose on secretion of transforming growth factor and extracellular matrix of cultured rat glomerular mesangial cells,the level of TGF β 1 、fibronection (FN),laminin (LAM),type Ⅳ collagen and type Ⅲ collagen in the tissue culture supernatant.Methods The culture of rat glomerular mesangial cells was established and the TGF β 1、FN、LAM、type Ⅳ collagen、type Ⅲ collagen were analyzed by a solid phase enzyme linked immunosorbent assay (ELISA).Results ①High concentration of glucose increased TGF β 1 biosynthesis and secretion.②High concentration of glucose selectively affected groups of functionally related proteins.Conclusion In vitro high glucose levels increased mesangial cell synthesis of the ECM and TGF β 1.The present studies suggest that mesangial cells may increase TGF β 1 and ECM synthesis in response to hyperglycemia and that this response could contribute to the accumulation of extracellular matrix responsible for diabetic glomerulosclerosis.