体外循环缺血再灌注后心肌缺血胰岛素抵抗与相关因子变化关系的研究

The study of the relationship between myocardial insulin resistance and related factors after cardiopulmonary bypass ischemia-reperfusion

目的:探讨体外循环(cardiopulmonary bypass,CPB)缺血再灌注后,冠状动脉血清胰高血糖素、生长激素及肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的变化与心肌胰岛素抵抗(insulin resistance,IR)的关系及其作用。方法:选择近年在我院行体外循环手术患者48例分为两组:组1主动脉阻断时间≤30min(n=24);组2主动脉阻断时间>30min(n=24)。于CPB转流3min(主动脉阻断前)、主动脉开放后15min、45min、75min、2h、4h及8h时分别采集桡动脉、冠状静脉窦血标本,比较对应时点血浆葡萄糖、胰岛素、胰高血糖素、生长激素、TNF-α及计算胰岛素抵抗指数(IRI)的变化。结果:血浆葡萄糖、胰岛素及胰岛素抵抗指数在缺血再灌注后显著不同程度增高,且于再灌注后15min达峰值,差异有统计学意义(P<0.05);心肌对葡萄糖的摄取、利用发生严重障碍,与1组比较,组2上述指标增高程度更重、持续更久,差异有统计学意义(P<0.05)。检测血清胰高血糖素、生长激素及TNF-α与血浆葡萄糖、胰岛素及胰岛素抵抗指数增高呈一致性,随主动脉阻断时间延长,其增高程度更重、持续更久,差异有统计学意义(P<0.05)。结论:在人体外循环中心肌缺血再灌注后冠状动脉血清胰高血糖素、生长激素及TNF-α分泌增加可能是心肌IR的重要因素之一。

Objective：Explore the relationship and role between coronary serum glucagon,growth hormone,tumor necrosis factor-a and myocardial insulin resistance after extracorporeal circulation ischemia-reperfusion.Methods：The 48 cases of cardiopulmonary bypass （CPB） patients based on different time of aortic blocked in CPB were divided into two groups：the group one （n =24）,the time of aortic blocked ≤ 30min ; the group two（n =24）,the time of aortic blocked ＞ 30mins.The blood specimens of artery and coronary sinus were collectied respectively before aortic cross-clamping of CPB （after 3mins of CPB） and after 15mins,45mins,75mins,2h,4h,8h of openning aorta.The changes of plasma glucose,insulin,glucagon,growth hormone and TNF-α were compared at corresponding time points and insulin resistance index （IRI） was calculated.Results：Plasma glucose,insulin and insulin resistance index increased significantly and reached their peaks after 15mins of ischemia-reperfusion,the difference was statistically significant（P ＜ 0.05） ;the uptake and use of myocardial glucose were obstacled seriously,the index of group two were higher degree and lasted longer compared with group one,the difference was statistically significant （P ＜ 0.05）.The increase the degree of serum glucagon,growth hormone,TNF-α,plasma glucose,insulin and insulin resistance index were consistent and their higher degree were heavier and lasted longer with aortic cross-clamping time,the differences were statistically significant （P ＜ 0.05）.Conclusion：The myocardial IR phenomenon exists in the human body during CPB;the increased secretion of coronary serum glucagon,growth hormone,and TNF-αmay be one of important factors of myocardial IR after myocardial ischemia and reperfusion.