Inhibition of superoxide anion-mediated impairment of endothelium by treatment with luteolin and apigenin in rat mesenteric artery.
This study was designed (i) to test the hypothesis that the endothelium-derived hyperpolarizing factor (EDHF) component of ACh-induced vasorelaxation and hyperpolarization of smooth muscle cells (SMCs) are impaired following exposure to superoxide anion, and (ii) to further investigate whether luteolin and apigenin induce vasoprotection at the vasoactive concentrations in rat mesenteric artery. Rat mesenteric arterial rings were isolated for isometric force recording and electrophysiological studies. Perfusion pressure of mesenteric arterial bed was measured and visualization of superoxide production was detected with fluorescent dye. 300 microM pyrogallol significantly decreased the relaxation and hyperpolarization to ACh. Luteolin and apigenin both induced vasoprotection against loss of the EDHF component of ACh-induced relaxation and attenuated the impairment of hyperpolarization to ACh. Oxidative fluorescent microtopography showed that either luteolin or apigenin significantly reduced the superoxide levels. The results suggest that superoxide anion impairs ACh-induced relaxation and hyperpolarization of SMC in resistance arteries through the impairment of EDHF mediated responses. Luteolin and apigenin protect resistance arteries from injury, implying that they may be effective in therapy for vascular diseases associated with oxidative stress.
Ma
Xin
X
Department of Physiology, Zhejiang University School of Medicine, Hangzhou 310058, China.
Li
Yan-fang
YF
Gao
Qin
Q
Ye
Zhi-guo
ZG
Lu
Xin-jiang
XJ
Wang
Hui-ping
HP
Jiang
Hui-di
HD
Bruce
Iain C
IC
Xia
Qiang
Q
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D047310:Apigenin / Q000494:pharmacology*; D001685:Biological Factors / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D047311:Luteolin / Q000494:pharmacology*; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology; D018384:Oxidative Stress / Q000187:drug effects; D010656:Phenylephrine / Q000494:pharmacology; D011748:Pyrogallol / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013481:Superoxides / Q000378:metabolism*; D014655:Vascular Resistance / Q000187:drug effects / Q000502:physiology; D014664:Vasodilation / Q000187:drug effects* / Q000502:physiology; D014665:Vasodilator Agents / Q000494:pharmacology*
D001685:Biological Factors; D014665:Vasodilator Agents; C067410:endothelium-dependent hyperpolarization factor; D011748:Pyrogallol; D013481:Superoxides; D010656:Phenylephrine; D047310:Apigenin; D047311:Luteolin; D000109:Acetylcholine