低温下尼可地尔对冠状动脉内皮细胞功能的影响

背景目前尼可地尔可(nicorandil)对改善供心的低温保存的良好效果已经证实.有关低温下其对冠状动脉内皮细胞影响也日趋受到关注.设计随机对照试验.目的探讨冷低温缺血期高钾溶液中尼可地尔对猪冠状动脉内皮细胞的影响及机制,为改善心脏移植期间供心的保存效果提供实验依据.地点、材料和干预本实验在北京阜外医院体外循环研究室完成,实验所用猪心来源于2000-06/09从北京大红门肉联厂随机选取的17只刚宰杀的生猪.将新鲜猪心外膜下冠状动脉前降支切成3段,长3mm,共42条血管环,随机分为6组,每组7条.在4℃条件下分别用重碳酸盐缓冲液(KH液,对照组)、高钾(20,50mmol/L,A,B组)溶液、添加尼可地尔(0.1 mmol/L)的KH液、高钾(20,50 mmol/L)溶液(C,D,E组)保存4h.主要观察指标前列腺素F2α引起冠状动脉最大预收缩强度;非受体介导钙离子载体引起内皮源性舒张(占预收缩高度的百分比).结果各组血管的收缩反应差异无显著性意义(P＞0.05);A,B,E组[(25.21±6.78)%,(35.97±6.81)%,(35.97±6.81)%]血管的舒张反应明显低于对照组[(62.03±9.65)%](F=28.621,P＜0.01),C,D组[(58.78±10.12)%,(57.56±10.38)%]组差异无显著性意义(P＞0.05).结论低温下尼可地尔对冠状动脉内皮源性超极化因子介导的血管舒张功能有保护作用.此结论可为心脏移植、心脏康复提供实验室依据.

Effects of nicorandilon the function of endothelium of coronary artery at hypothermia

BACKGROUND: It has been confirmed that nicorandil(NCR) has good cardioprotective effect under hypothermia. Moreover, the effects of NCR on endothelium of coronary artery at hypothermia have attracted much attention.DESIGN: Randomly controlled experiment.OBJECTIVE: To study the effects of NCR in high potassium solution on hypothermic ischemia preservation of porcine coronary endothelium and its mechanism for providing experimental evidences for improving clinical cardioprotection during heart transplantation.SETTING, PARTICIPANTS and INTERVENTIONS: This experiment was carried out in the Department of Extracorporeal Circulation, Fuwai Hospital in Beijing. Porcine coronary arteries were randomly selected from seventeen porcine hearts that were harvested in a Beijing Dahongmeng abattoir. Anterior descending branch of coronary artery was cut into 3 pieces of 3 mm. Totally 42 vascular circles were randomly divided into six groups, 7 in each. And then, the arteries were kept in bicarbonate buffer [ebs-Henseleit (KH, control group) ], high potassium solution(20, 50 mmol/L, group A or B) or KH solution plus NCR(0. 1 mmol/L), high potassium solution(20,50 mmol/L, group C, D or E)for 4 hours.MAIN OUTCOME MEASURES: Maximal preconcentration intensity of coronary artery induced by prostaglandin F2α; Endothelium-derived hyperpolarizing factor(EDHF) -mediated relaxation induced by calcium ionophore (percentage of preconcentration intensity).RESULTS: There was no significant meaning in contractile response difference( P ＞ 0. 05 ); EDHF-mediated relaxation of group A, B and E [ (5.21 ± 6.78) %, (35.97 ± 6. 81 )% and(35.97 ± 6. 81 ) % respectively] was significantly lower than that of control group [ (62.03 ± 9.65)% ](F=28.621, P ＜0.01) .Difference in the group C and D [(58.78 ± 10. 12)%, (57.56 ± 10. 38)% respectively] had no significant meaning(P ＞ 0.05).CONCLUSION: NCR has protective effect on EDHF-mediated coronary relaxation at hypothermia. This conclusion provides experimental evidences for heart transplantation and rehabilitation.Li SK, Long C, Cheng BC, He W, Liu TW, Jiang H. Effects of nicorandil on the function of endothelium of coronary artery at hypothermia. Zhongguo Linchuang Kangfu 2004; 8 (33): 7596 -7(China) [ www. zglckf. com]INTRODUCTIONPrevious researches showed that nicorandil(NCR) could ameliorate cardioprotection at hypothermia, and was beneficial for the recovery of coronary artery flow[1]. However, reports on the effect of NCR on coronary artery endothelial cell function are scarce. The author took porcine coronary artery as the object of study and used the organ slot method[3] to explore NCR protective effect on EDHF-mediated vasodilatational function in high potassium solution at hypothermia and provide experimental evidences for heart transplantation and rehabilitation.