Chrysin relaxed the contractions induced by noradrenaline in isolated endothelium-intact rat aortic rings (IC50 = 16 ± 4 μM). Endothelium removal and NG-nitro-L-arginine methyl ester inhibited this relaxant effect. Chrysin potentiated the relaxation to acetylcholine under control conditions or after incubation with the superoxide anion generator hypoxanthine/xanthine oxidase. It also potentiated the relaxation induced by 3-morpholino-sydnonimine, sodium nitroprusside, and 8-bromoguanosine-3′:5′-cyclic-monophosphate. Therefore, vasorelaxation induced by chrysin in the rat aorta is endothelium- and NO-dependent. This effect is mediated by the prevention of O2--induced inactivation of endothelial derived NO and also by the potentiation of cGMP-induced vasodilatation.
Abbreviations
L-NAME:NG-nitro-L-arginine methyl ester
NO:nitric oxide
SIN-1:3-morpholino-sydnonimine
References
1
Kühnau J.
The flavonoids. A class of semi-essential food components: their role in human nutrition.
World Review of Nutrition and Dietetics.
1976;
24
117-91
2
Siess M H, Le Bon A M, Canivenc-Lavier M C, Amiot M J, Sabatier S, Aubert S Y,. et al .
Flavonoids of honey and propolis: Characterization and effects on hepatic drug-metabolizing enzymes and benzo[a]pyrene-DNA binding in rats.
Journal of Agricultural and Food Chemistry.
1996;
44
2297-301
3
Hertog M GL, Hollman P CH, Katan M B.
Content of potentially anticarcinogenic flavonoids of 28 vegetables and 9 fruits commonly consumed in the Netherlands.
Journal of Agricultural and Food Chemistry.
1992;
40
2379-83
4
Chan E CH, Pannangpetch P, Woodman O L.
Relaxation to flavones and flavonols in rat isolated thoracic aorta: mechanism of action and structure-activity relationships.
Journal of Cardiovascular Pharmacology.
2000;
35
326-33
5
Duarte J, Pérez-Vizcaino F, Utrilla M P, Jiménez J, Tamargo J, Zarzuelo A.
Vasodilating effects of flavonoids in rat aortic smooth muscle: structure-activity relationships.
General Pharmacology.
1993;
24
857-62
6
Herrera M D, Zarzuelo A, Jimenez J, Marhuenda E, Duarte J.
Effects of flavonoids on rat aortic smooth muscle contractility: structure-activity relationships.
General Pharmacology.
1996;
27
273-7
7
Jiménez R, Andriambeloson E, Duarte J, Andriantsitohaina R, Jiménez J, Pérez-Vizcaino F ,. et al .
Involvement of thromboxane A2 in the endothelium-dependent contractions induced by myricetin in rat isolated aorta.
British Journal of Pharmacology.
1999;
127
1539-44
9
Fitzpatrick D F, Hirschfield S L, Coffey R G.
Endothelium-dependent vasorelaxing activity of wine and other grape products.
American Journal of Physiology.
1993;
265
H774-78
11
Gryglewski R J, Palmer R M, Moncada S.
Superoxide anion is involved in breakdown of endothelium-derived vascular relaxing factor.
Nature.
1986;
320
454-6
12
Mian K B, Martin W.
Differential sensitivity of basal and acetylcholine-stimulated activity of nitric oxide to destruction by superoxide anion in rat aorta.
British Journal of Pharmacology.
1995;
115
993-1000
14
Lipton S A, Choi Y -H, Pan Z -H, Lei S Z, Chen H -S, Sucher N J,. et al .
A redox-based mechanism for the neuroprotective and neurodestructive effects of nitric oxide and related nitroso-compounds.
Nature.
1993;
364
626-32
