Objective: To observe the effects of total flavonoids of tartary buckwheat on IRS-2 in EA.hy926 cells in the presence of palmitic acid. Method: EA.hy 926 cells were cultured in vitro and divided into control group

insulin resistance induced by palmitic acid group

total flavonoids of tartary buckwheat group and metformin group randomly. Each group combined 10% FBS ADMA complete medium and insulin (50 nmol·L-1)

compared with control group

other groups contain palmitic acid (600 μmol·L-1)

and total flavonoids of tartary buckwheat group contain total flavonoids of tartary buckwheat flavonoids (125 mg·L-1)

metformin group contain metformin (2 mmol·L-1). The IRS-2 mRNA and protein expression levels were determined by RT-PCR and Western blot respectively. Result: Compared with control groups

the expression levels of IRS-2 mRNA and protein were significantly lower in insulin resistance group (P<0.05).the expresssion levels of IRS-2 mRNA and protein of control group were (1.203±0.040 )and (1.164±0.034)

and insulin resistance induced by palmitic acid group were (0.611±0.022) and (0.580±0.006)

Compared with insulin resistance group

the IRS-2 mRNA and protein expression were markedly increased in both total flavonoids of tartary buckwheat group and metformin group (P<0.05)

and there is no significant difference between two groups. the expression levels of IRS-2 mRNA and protein of total flavonoids of tartary buckwheat group were (0.904±0.157) and (0.845±0.029)

and metformin group randomly were (0.890±0.054) and (0.841±0.006). Conclusion: Total flavonoids of tartary buckwheat effectively promotes the expression of IRS-2 mRNA and protein in endothelial cells under palmitic acid stimulation.