Endothelium-independent vasorelaxant effect of puerarin on rat thoracic aorta
Dong, K.; Tao, Q.-m.; Xia, Q.; Shan, Q.-x.; Pan, G.-b.
Zhongguo Zhong Yao Za Zhi 29(10): 981-984
2004
ISSN/ISBN: 1001-5302 PMID: 15631089 Document Number: 582104
To investigate the vasorelaxant effect of puerarin in rat aortic rings and the mechanism. The isolated thoracic aortic rings of male Sprague-Dawley rats were mounted on the organ bath and the contractile responses of the vessel were recorded. Puerarin completely relaxed the contractions induced by phenylephrine in a concentration-dependent manner in endothelium-intact and endothelium-denuded rat aorta, but it had no effect on those preconstricted by a high concentration of potassium chloride (KCl, 60 mmol x L(-1)). The relaxant effect of puerarin was significantly inhibited by pretreatment of endothelium-denuded aorta with potassium channel antagonists tetraethylammonium, 4-aminopyridine but not glibenclamide. Puerarin induces an endothelium-independent relaxation in rat aortic rings. The mechanisms may involve the reduction in Ca2+ influx through the calcium channels operated by alpha-adrenergic receptor and the activation of the potassium channels (Kv and BKca, but not KATP).