Quercetin could obviously enhance the sensitivity of MCF-7/ADR cells to adrimary,fold reversal(FR)was3.19.Positivity of P-glycoprotein was decreased after exposed to quercetin.

• 槲皮素能提高MCF-7/ADR细胞对阿霉素的敏感性；逆转倍数为3.；19；并能降低MCF-7/ADR细胞Pgp的表达。