Duarte J, Pérez-Vizcaíno F, Zarzuelo A, Jiménez J, Tamargo J
Department of Pharmacology, School of Pharmacy, University of Granada, Spain.
Eur J Pharmacol. 1993 Aug 3;239(1-3):1-7. doi: 10.1016/0014-2999(93)90968-n.
The effects of quercetin were studied on contractile responses induced by noradrenaline, high KCl, Ca2+ and phorbol 12-myristate,13-acetate in rat aortic strips and on spontaneous mechanical activity in rat portal vein segments. Quercetin, 10(-6)-10(-4) M, inhibited in a concentration-dependent manner the contractions induced by noradrenaline, high KCl and Ca2+, this effect being observed when the drug was added before or after the induced contractions. The spontaneous myogenic portal activity was also inhibited. Mechanical removal of endothelium did not affect the relaxant effects of quercetin on noradrenaline-induced contractions. In addition, at the same range of concentrations, quercetin also relaxed the contractions induced by phorbol 12-myristate,13-acetate. Quercetin1 10(-5) and 5 x 10(-5) M, increased the aortic cyclic AMP content. However, pretreatment with 10(-7) M isoprenaline did not modify the relaxant effects of quercetin on noradrenaline-induced contractions and quercetin did not modify the relaxant effects of forskolin, which suggested that the vasodilator effects of quercetin were not mediated by inhibition of cyclic AMP phosphodiesterases. In conclusion, in isolated rat aorta quercetin produced a vasodilator effect that seems to be mainly related to the inhibition of protein kinase C. However, and since this drug exerts multiple biochemical effects, inhibition of other transduction pathways may be involved in this effect.
研究了槲皮素对大鼠主动脉条中去甲肾上腺素、高钾、钙离子和佛波酯12 -肉豆蔻酸酯13 -乙酸酯诱导的收缩反应以及大鼠门静脉段自发机械活动的影响。10(-6)-10(-4)M的槲皮素以浓度依赖性方式抑制去甲肾上腺素、高钾和钙离子诱导的收缩，在诱导收缩前或后加入该药物时均观察到这种效应。门静脉的自发肌源性活动也受到抑制。机械去除内皮不影响槲皮素对去甲肾上腺素诱导收缩的舒张作用。此外，在相同浓度范围内，槲皮素也能舒张佛波酯12 -肉豆蔻酸酯13 -乙酸酯诱导的收缩。10(-5)和5×10(-5)M的槲皮素可增加主动脉环磷酸腺苷（cAMP）含量。然而，用10(-7)M异丙肾上腺素预处理并未改变槲皮素对去甲肾上腺素诱导收缩的舒张作用，且槲皮素也未改变福斯高林的舒张作用，这表明槲皮素的血管舒张作用不是通过抑制环磷酸腺苷磷酸二酯酶介导的。总之，在离体大鼠主动脉中，槲皮素产生血管舒张作用，这似乎主要与抑制蛋白激酶C有关。然而，由于该药物具有多种生化作用，其他转导途径的抑制可能也参与了这一效应。
