Objective: To explore stimulates the proliferation of transforming growth factor-β1 (TGF-β1) in vitro rat lung fibroblasts. Method: The rat lung fibroblast were cultured in vitro

the 4th generation of cells in logarithmic growth phase were used to proliferation experiments. These cells were randomly divided into five groups:serum-free Dulbecco's modified Eagle medium(DMEM) group

10.0

5.0

2.5

1.25 μg·L-1 of TGF-β1 DMEM group. We selected the optimal stimulation point of TGF-β1 in three different stimulation time points of application(24

48

72 h) by the tetrazolium salt colorimetric method (MTT method) to explore the TGF-β1 stimulating rat lung fibroblast proliferation optimal concentration and the best time point by statistical analysis of variance and multiple comparison. Result: TGF-β1 in 24 h time point directly stimulated the 5 different groups of SD rat lung fibroblast proliferation based on MTT results by analysis of variance

the five groups were no significant difference. In 48 h time point

by the non-parametric test

P<0.05

these groups were significantly different.Seventy-two h time point

by analysis of variance

P<0.05

these groups were significantly different; further two multiple comparisons: control group

10.0

2.5 μg·L-1 group

P<0.05

2.5

1.25 μg·L-1were P<0.01

the rest of the group

P>0.05. Conclusion: 48 h

72 h time point were observed to promote the proliferation of TGF-β1

and the best proliferative activity of stimulate concentration and time point of TGF-β1 were 2.5 μg·L-1

72 h.In this concentration and time point

rat lung fibroblast proliferated significantly.