【摘要】 本文研究了CY对家兔离体血管平滑肌的舒张作用。采用家兔离体胸主动脉为标本研究CY的舒血管作用。CY(3×10-3mM～3mM)可以舒张由肾上腺素、去甲肾上腺素、高钾和BaCl2引起收缩的血管平滑肌,EC50值分别为0.31±0.11,0.19±0.03,0.20±0.04和0.25±0.04mM.CY(0.01mM、0.1mM、1mM)剂量依赖性地抑制NE、KCl或CaCl2引起的的累积收缩量效曲线并呈非竞争性.在无钙液中CY能剂量依赖性的减弱由NE引起的位相性(第一时相)收缩,与维拉帕米有相似作用。因此,CY可能是通过阻断电压依赖性Ca2+通道舒张胸主动脉环。抑制细胞内钙的释放可能是CY主要的血管舒张作用机制之一。更多还原

【Abstract】 The purpose of this study was to examine the relaxation effect of CY on the vascular smooth muscle(VSM)from rabbits.Experiments were carried out on isolated thoracic aorta of rabbits.CY(3×10-3 mM-3 mM)could relax the VSM preparations pre-contracted by adrenaline(AD),noradrenaline(NE),high-K+ solution or BaCl2 with respective EC50 values of(0.31±0.11)mM,0.19±0.03 mM,0.20±0.04 mM and 0.25±0.04 mM.Moreover,CY(10-2 mM,0.1 mM and 1 mM)inhibited norepinephrine(NE),CaCl2 and KCl-induced vasoconstriction in a concentration dependent manner.The phasic contraction produced by NE was concentration dependently attenuated with CY(10-2 mM,0.1 mM and 1 mM)in calcium-free medium,similar to that caused by verapamil.The present findings suggest that CY relaxed thoracic aortic rings by blocking voltage-dependent Ca2 + channels.The inhibition of intracellular Ca 2+ release may be one of the main vasorelaxant mechanisms of CY.更多还原