Abstract: Human embryonic lung diploid fibroblasts(HELDF)in vitro were used as experiment materials.Whe the cells were subcultured for 27 generations,they were divided into two groups,medicine-treated group(B)which was supplemented with Astragalus membranaceus Bunge(AMB),and control group(C).The two groups were subcultured at same condition until the cells ceased proliferating.In the meantime,at regular intervals,the proliferation a-bility and SOD contents of two groups were determined with the flow cytometry and the chemiluminescence method respectively.The routine chromosome test and the measurement of the survival time in one generation were also taken at same time.Our results showed that the cells of group B were subcultured for 77 generations while the cells of group C only for 52 generations.The HELDF of two groups maintained their diploidy from the beginning of subculture to the end.The proliferation ability,SOD contents and the survival time of two groups decrease gradually with the increase of generations.But at the same generation the proliferation ability,SOD contents and the survival time of group B was higher than those of group C and this difference became more obvious with the increase of generations.

Key words: Astragalus membranaceus Bunge, human embryonic lung diploid fibroblasts, aging, proliferation, superoxide dismutase, chromosome