Objective: To observe the effects of Sini San and Liuwei Dihuang Wan on the proliferation and the expression of c-myc mRNA and CyclinD1 mRNA of neural stem cells(NSCs) in vitro. Method: NSCs of the thirrd generation in good condition were resuspended

blew

struck and cultured in medium with the density of 1×105/mL and in incubator with 5% CO2 and 95% humidity at 37℃.The cultured NSCs were divided into five groups: the normal control group

the low doses of and the high doses of Sini San group

the low doses of and the high doses of Liuwei Dihuang Wan group. All NSCs in five groups were cultivated with DMEM/F12(1: 1) medium for 4 days. The culture medium was changed 30% every other day. The low concentration of Sini San decoction with 0.133 g crude drug per liter

the high concentration of Sini San decoction with 0.267 g crude drug per liter

the low concentration of Liuwei Dihuang Wan decoction with 0.208 g crude drug liter and the high concentration of Liuwei Dihuang Wan decoction with 0.416 g crude drug per liter were added respectively into the medium in the low doses of Sini San group

the high doses of Sini San group

the low doses of Liuwei Dihuang Wan group and the high doses of Liuwei Dihuang Wan group. The proliferation of cells was detected by 5-bromo-2-deoxy uridine(BrdU) labeling fluorescence immunocytochemistry every day. The relative expression of c-myc mRNA and cyclinD1 mRNA was detected by fluorescence real-time quantitative PCR in each group. Result: The results of BrdU labeling fluorescence immunocytochemistry:the proliferation of cells in the low and high doses of Liuwei Dihuang Wan group was more obvious than that in the low doses of Sini San group and the high doses of Sini San group(P<0.01).There was no obvious difference in the proliferation of cells between the low doses of Sini San group

the high doses of Sini San group and normal control group. Results of fluorescence real-time quantitative PCR:the relative expression of c-myc mRNA and CyclinD1 mRNA in the low doses of Liuwei Dihuang Wan group and the high doses of Liuwei Dihuang Wan group was higher obvious than that in the low doses of Sini San group and the high doses of Sini Powder group(P<0.01).There was no obvious difference in the relative expression of c-myc mRNA and CyclinD1 mRNA between the low doses of Sini San group

the high doses of Sini San group and normal control group. Conclusion: Compared with Sini San

Liuwei Dihuang Wan has a significant stimulative effect on the proliferation of NSCs or the expression of c-myc mRNA and CyclinD1 mRNA.