单纯缺血预处理对兔未成熟心脏不足以提供保护作用  

Ischemic preconditioning in immature rabbit hearts

作　　者：朱斌[1] 闵苏[1] 龙村[2] 

机构地区：[1]重庆医科大学附属第一医院麻醉科,630042 [2]中国医学科学院中国协和医科大学心血管病研究所阜外心血管病医院麻醉体外循环研究室

出　　处：《中华麻醉学杂志》2001年第2期97-99,共3页Chinese Journal of Anesthesiology

摘　　要：目的　探讨单纯缺血预处理 (IPC)对兔未成熟心脏缺血再灌注损伤的影响。方法　利用Langendorff模型灌注幼兔 (14 2 1d)离体心脏 ,5min缺血、10min再灌的IPC处理后 ,观察其在生理体温 (39℃ )下接受 30min缺血、40min复灌的血液动力学、冠脉流出液心肌酶及心肌能量的变化。结果　复灌后IPC组与对照组在心率 (HR)、冠脉流出量 (CF)、左室发展压 (LVDP)、左室最大上升和下降速率 (±dp/dt)恢复率及室性心律失常发生率无明显差别 ,肌酸磷酸激酶同工酶 (CK MB)漏出量有增多趋势。而IPC组在全心停灌后心脏缺血跳动时间明显延长 (P <0 0 1) ,再灌注末心肌ATP含量显著减少 (P <0 0 0 1)。结论　单纯缺血预处理不能保护未成熟心脏免受心肌缺血再灌注损伤 ,反而可导致心肌细胞的损伤 ;其原因可能与全心缺血后 。Objective Protection afforded by ischemic preconditioning (IPC) against myocardial ischemia in adult heart has been investigated. This study was designed to examine the effects of IPC on myocardial tolerance to ischemia in immature hearts.Methods The aorta of isolated immature rabbit heart (14-21d old) was connected to Langendorff preparation within 30 s after excision. The hearts were perfused with oxygenated (95%O 2:5%CO 2) Krebs-Henseleit buffer(KHB) at 60 cmH 2O. 16 immature rabbit hearts were equally divided into 2 groups: control group and IPC group. In IPC group the hearts were first subjected to IPC stimulus consisting of 5 min global ischemia followed by 10 min reperfusion. The hearts in both groups were made globally ischemic for 30 min(no perfusion) followed by 40 min reperfusion. At the end of 40 min reperfusion the hearts were harvested for ATP analysis. The coronary flow(C), HR, left ventricle developed pressure(LVDP) and ±dp/dt were monitored and recorded before ischemia and at 5,10,20,30 and 40 min of reperfusion, and calculated as % of pre-ischemia levels. Coronary flow was collected before and after reperfusion for CK-MB determination.Results There were no statistically significant differences in the four parameters between the two groups. Arrhythmia scores were also comparable betweeen the two groups. The CK-MB leakage in IPC group was increased but not significantly different from that in control group. The ATP levels of myocardium at the end of reperfusion was significantly lower than that in the control group [(123.85±17.42)μg/g versus (167.21±16.53)μg/g].Conclusions IPC can not protect immature rabbit hearts from ischemia-reperfusion injury. On the contrary it may lead to myocardial injury due to more energy consumption.

关 键 词：缺血预处理 心肌 心肌再灌注损伤 心脏外科手术 

分 类 号：R614[医药卫生—麻醉学]