哇巴因对豚鼠主动脉环平滑肌作用及与Ca^(2+)、去甲肾上腺素的相互关系

Effect of ouabain on the aortic rings of guinea pig and its interactions with Ca^(2+), norepinephrine

目的 观察哇巴因 (ouabain ,Oua)对豚鼠血管平滑肌的作用 ,及其与Ca2 + 和去甲肾上腺素 (NE)的相互作用关系。方法 利用豚鼠离体胸主动脉环 ,观察药物对其张力的影响。结果 无论有无内皮存在 ,Oua均能剂量依赖性地直接收缩血管平滑肌。在无钙溶液中 ,Oua不能引起血管收缩。Oua可使NE的量效曲线平行左移 ,Emax不变 ;Oua可使CaCl2 的量效曲线左移上移 ,Emax 增大。硝苯地平和维拉帕米可使Oua所致的血管收缩曲线下降。结论Oua所致的血管收缩作用不依赖于血管内皮的存在 ,但依赖于细胞外钙 ,并且能被钙拮抗剂所拮抗 ;NE与Oua ,Ca2

Aim To observe the effects of ouabain on vascular smooth muscle (VSM) of the guinea pig and its interactions with Ca 2+ and norepinephrine (NE). Methods Using isolated thoracic aortic ring of the guinea pig, the degrees of contractile activity of drugs were recorded. Results Ouabain showed a direct contractile effect in a concentration-dependent manner on thoracic aortic ring of guinea pig. Ouabain shifted the NE dose-response curve to the left without changing in the maxium response. Ouabain shifted ...