摘要Background In China the ginseng root began to be used in medicine over 2000 years ago. Ginsenosides are the most important component isolated from ginseng. The authors investigated the effect of ginsenoside Rg1 on the spectrum of gene expression in the endothelial cells stimulated by TNF-α and further explored the potential molecular mechanism of endothelial protection by ginsenoside Rg1.Methods Nitric oxide (NO) production in the cultured human umbilical vein endothelial cells(HUVECs) was measured by using an NO assay kit. A home-made oligonucleotide microarray containing approximately 400 cardiovascular disease-related genes was constructed. The alteration of the spectrum of gene expression induced by ginsenoside Rg1 in HUVECs which were activated by TNF-α were detected by oligonucleotide microarray analysis.Results NO production in HUVECs was decreased significantly after TNF-α treatment, while pretreatment with ginsenoside Rg1 enhanced NO production in TNF-αstimulated HUVECs. Ginsenoside Rg1 affected the expression levels of genes involved in vascular constriction, cell adherence, coagulation, cell growth and signal transduction in TNF-αstimulated HUVECs.Conclusions Ginsenoside Rg1 could enhance NO production and the expression of eNOS mRNA in TNF-α stimulated HUVECs. Ginsenoside Rg1 regulated sets of genes in endothelial cells and protected endothelial cells from TNF-αactivation. Microarray analysis provided us with valuable insights into the atheroprotective mechanism by gingsenoside Rg1.