尼可地尔对大隐静脉舒张功能的保护作用

The Protective Effect of Nicorndil Vasodilation of Saphenous Vein

目的 探讨不同温度下尼可地尔 (NCR)和罂粟碱对冠状动脉旁路移植术 (CABG)大隐静脉血管内皮超极化因子 (EDHF)介导血管舒张功能的影响。方法 取材于临床 CABG剩余的新鲜大隐静脉。采用器官槽法分别检测用重碳酸盐缓冲液 (KH )、含 1.2 m mol/ L罂粟碱的 KH及加入 0 .1mm ol/ L NCR和 1.2 m mol/ L罂粟碱溶液的 KH在不同温度 (3 7℃、2 7℃、2 0℃ )有氧条件下浸泡血管环 1h后 ,再用 7μm ol/ L吲哚美辛 (Indo)和 3 0 0μm ol/ L N-硝基 - L -精氨酸 (L NNA )作用后 ,检测 3 0 nmol/ L U46 6 1 9及不同浓度 A2 31 87引发的血管收缩舒张反应。结果 大隐静脉血管遇冷收缩 ,收缩的程度随温度的降低而加深 ;不同温度下 ,与单独浸泡于 KH中的血管环相比 ,浸泡于同样温度下的罂粟碱溶液中的 A2 31 87引发的血管舒张反应明显减低 ,浸泡于含 NCR的 1.2 mm ol/ L罂粟碱溶液血管舒张反应差异无显著性。结论 随温度的降低 ,大隐静脉血管张力增高 ,低温状态下 ,NCR对 EDHF介导血管舒张功能仍有保护作用 ,罂粟碱保护作用消失 ,加入了 NCR的罂粟碱溶液仍能舒张血管 。

OBJECTIVE To investigate the effect of nicorandil(NCR) and papaverine on endothelium derived hyperpolarizing factor (EDHF) mediated saphenous relaxation under different temperatures in patients undergoing coronary artery bypass grafting (CABG).METHODS A fresh saphenous vein obtained from CABG was cut into 3mm long rings. The rings were randomly divided into three groups. The tension of the coronary rings was studied by the organ chamber technique. the rings were incubated for 1 hour in aerobic Krebs Herseleit solution(KH); KH with 1.2 mmol/L papaverine and KH with 1.2 mmol/L papaverine plus 0.1 mmol/L NCR, under 37℃, 27℃ and 20℃. The contraction response to 30 nmol/L U 46619 and the relaxation response to A 23187 were then assessed in presence of 7(mol/L Indomethacin(Indo) and 300(mol/L N Nitro L Arginine(LNNA). RESULTS Saphenous vein contracted significantly under lower temperature (either 27℃ or 20℃). Vascular relaxation in KH with papaverine, but not in KH with papaverine plus NCR, declined significantly, compared with KH only. CONCLUSIONS The tension of the saphenous vein increases as the temperature decreases. The protective effect of NCR on vascular relaxation mediated by EDHF is kept under hypothermia. The effect of papaverine supplied with NCR on vascular relaxation is still available under hypothermia. This effect can reduce the contracture of vascular bypass. Vascular contraction response to hypothermia should be avoided in clinical practice.