Objective :To investigate the effects of astragalus injection on cell cycle and in vitro proliferation of rabbit adipose-derived mesenchymal stem cells (ASCs). Method :ASCs were obtained from an experimental rabbit and cultured. Multi experimental and a control group were designed. Different concentrations of astragalus injection were added to the culture fluid in the experimental group

while a conventional culture method was employed in the control group. The distribution of the cell cycle was measured by flow cytometry and the proliferation rates of ASCs by MTT

and compared between the experimental and the control group. Result :After 24 hours of culture

the number of the cells during the proliferative phase was increased significantly from (65.3±4.8)% for the control group to (72.6±5.7)% for the experimental group

and the differences between each experimental and the control groups were not significant. After 48 hours

the optical density was (2.273±0.100)-(1.983±0.125) in each experimental group at 0.390 6-200 g·L-1 of astragalus

while (1.341±0.424) in the control group

and the differences between each experimental and the control groups were significant (P<0.01)

suggesting astragalus at the concentrations within the experimental rang might have big promotion on proliferation of ASCs. Conclusion :Astragalus injection has significant promotion effect on the in vitro proliferation of rabbit ASCs.