Wang Hui-ping, Qiu Fu-yu, Chen Cheng, Zhao Meng-hui, Lu Yuan, Xia Qiang
Department of Physiology, Zhejiang University School of Medicine, Hangzhou 310031, China.
Zhongguo Ying Yong Sheng Li Xue Za Zhi. 2006 Aug;22(3):274-7.
To investigate the mechanisms of vasodilatation of plant-derived estrogen biochanin A.
Isolated aortic ring preparations from Sprague-Dawley rats were suspended in individual organ baths. The tension was measured isometrically.
Biochanin A at the range of 10(-9)-10(-4) mol/L provoked concentration-dependent and endothelium-independent relaxation of the rings constricted by phenylephrine (10(-5) mol/L). Biochanin A caused concentration-dependent relaxation of denuded rings precontracted with KCl (6 x 10(-2) mol/L). Glibenclamide (3 x 10(-6) mol/L), a selective inhibitor of ATP-sensitive potassium channels, and tetraethylammonium (5 x 10(-3) mol/L), a Ca2+ -activated K+ channel inhibitor, significantly attenuated the relaxation induced by biochanin A. The vasoconstriction induced by phenylephrine was decreased by biochanin A in Ca2+ -free medium.
The endothelium-independent relaxation of thoracic aorta induced by biochanin A might be mediated by ATP-sensitive K+ channels, Ca2+ -activated K+ channels and intracellular Ca2+ release from sarcoplasmic reticulum.
研究植物源雌激素黄豆苷元的血管舒张机制。
将来自Sprague-Dawley大鼠的离体主动脉环标本悬挂于单个器官浴槽中。采用等长方式测量张力。
浓度范围为10⁻⁹ - 10⁻⁴ mol/L的黄豆苷元可引起由去氧肾上腺素（10⁻⁵ mol/L）收缩的血管环出现浓度依赖性和非内皮依赖性舒张。黄豆苷元可使预先用氯化钾（6×10⁻² mol/L）预收缩的去内皮血管环出现浓度依赖性舒张。格列本脲（3×10⁻⁶ mol/L），一种ATP敏感性钾通道的选择性抑制剂，以及四乙铵（5×10⁻³ mol/L），一种Ca²⁺激活的K⁺通道抑制剂，可显著减弱黄豆苷元诱导的舒张。在无钙培养基中，黄豆苷元可降低去氧肾上腺素诱导的血管收缩。
黄豆苷元诱导的胸主动脉非内皮依赖性舒张可能由ATP敏感性钾通道、Ca²⁺激活的钾通道以及肌浆网释放细胞内钙介导。
