摘要
目的本研究组在前期研究中证实雷帕霉素会减弱缺氧预处理对原代乳鼠心肌细胞的保护作用,本研究拟在整体心脏水平验证这一现象并探讨其机制。方法建立Langendorff大鼠离体心脏模型,分别测定并分析缺血再灌注(I/R)、缺氧预处理(HPC)、雷帕霉素干预后缺氧预处理(Rapa+HPC)三组的血流动力学指标,验证雷帕霉素对缺氧预处理心肌保护效应的影响,应用qRT-PCR技术测定HIF1α与mTOR的mRNA表达水平。结果 Rapa+HPC组再灌注后30min,60min心率与I/R组差异无统计学意义,Rapa+HPC组LVDP、dp/dt虽较HPC组降低(p<0.05),但仍高于I/R组。HPC组HIF1α mRNA与mTOR mRNA水平高于I/R(16.96±1.82 vs 1.01±0.13,p<0.05;1.99±0.32 vs 1.05±0.40,p<0.05),及Rapa+HPC组(1.56±0.36,p<0.05;0.63±0.06,p<0.05)。结论缺氧预处理早期可产生心肌保护作用,促进缺血再灌注后心脏功能的恢复。雷帕霉素会减弱缺氧预处理的心肌保护效应。这一早期保护作用涉及HIF1α与mTOR表达增加,雷帕霉素可通过HIF1α与mTOR在这一过程中的表达,减弱缺氧预处理早期心肌保护作用。
Objective It＇s has proved rapamycin could reduce the cardioprotection effect of hypoxia preconditioning in cardiomyocytes of primary neonatal rats. In this study, we want to confirm this phenomenon in whole heart model and find out its mechanism. Methods Langendorff model was built. Hemodynamic index of I/R group, HPC group and Rapa ＋ HPC group were measured and analyzed. Hemodynamic results were used to prove the cardioprotective effect. qRT-PCR was used to quantified HIF1αmRNA and mTOR mRNA level. Results In Langendorff model, there is no significant difference between priming Rapa＋HPC for 30 min and for 60 min, the value of LVDP and dp/dt of Rapa＋HPC group is a little lower than that of HPC group （p〈0.05）, but it still higher than that of I/R group. In HPC group, the level of HIF1αmRNA and mTOR mRNA is higher than that of I/R group （16.96 ±1.82 vs 1.01 ± 0.13,p〈0.05;1.99±0.32 vs 1.05±0.40,p〈0.05）, and Rapa＋HPC group （1.56±0.36,p〈0.05;0.63±0.06,p〈0.05）. Conclusion Early period of hypoxic preconditioning could produce myocardial protect effect, and promote the recovery of cardiac function after ischemia. Rapamycin can reduce effect of myocardial protect. This effect refers to the increase of HIF1αand mTOR, rapamycin can express through HIF1αand mTOR, to reach the effect of decreasing of myocardial protect in the period of pretreatment of ischemia.
出处
《新疆医学》
2016年第6期607-610,共4页
Xinjiang Medical Journal
基金
中国医师协会麻醉学医师分会"人福"青年麻醉医师科研基金项目(220150800009)
