Effects of phytoestrogens and 17beta-estradiol on vasoconstriction elicited by reactive oxygen species.
To study the effects of different reactive oxygen species (ROS) on the resting tension of porcine coronary artery rings and to identify the effects of genistein (GEN), resveratrol (RES) and 17beta-estradiol (EST) on ROS-elicited vasoconstriction, porcine coronary rings were prepared and mounted in an organ bath and, after an equilibration period, the changes induced by the drugs were observed. Rings with intact endothelium showed an obvious but slow contraction after treatment with xanthine (100 microM)/xanthine oxidase (20 mU x mL(-1)) (X/XO) whereas endothelium-denuded rings showed no effects. H2O2 (200 microM) induced a fast and transient contraction in endothelium-denuded rings and failed to do so in intact-endothelium rings. Like superoxide dismutase (SOD, 200 U x mL(-1)), GEN (1 microM) and RES (1 microM) significantly inhibited contractile response evoked by X/XO, however in contrast to GEN and RES, EST (1 microM) had no obvious effect. GEN (30 microM) and RES (30 microM), like catalase (CAT, 800 U x mL(-1)), markedly attenuated the contraction elicited by H2O2. The results demonstrate that GEN and RES have distinct inhibitory effects on vasoconstriction induced by O2*- generated by X/XO and H2O2, and their actions are clearly greater than to that of EST.
Zhang
Peng
P
Department of Physiology, College of Basic Medicine, Lanzhou University, Lanzhou, People's Republic of China.
Li
Hong-Fang
HF
Tian
Zhi-Feng
ZF
Qiu
Xiao-Qing
XQ
Wu
Jin-Xia
JX
Jia
Zhong-Jian
ZJ
D000818:Animals; D002417:Cattle; D003331:Coronary Vessels / Q000187:drug effects; D004958:Estradiol / Q000494:pharmacology*; D019833:Genistein / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000037:antagonists & inhibitors / Q000494:pharmacology; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D010100:Oxygen / Q000494:pharmacology; D048789:Phytoestrogens / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology; D013482:Superoxide Dismutase / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects*
D048789:Phytoestrogens; D017382:Reactive Oxygen Species; D013267:Stilbenes; D004958:Estradiol; D006861:Hydrogen Peroxide; D019833:Genistein; D013482:Superoxide Dismutase; D000077185:Resveratrol; D010100:Oxygen