摘 要 目的：在传统心脏停搏液中加入L-精氨酸、腺苷和组氨酸，观察改良心脏停搏液对心肌缺血/再灌注损伤(I/R)的保护作用。方法：采用随机双盲对照法，12只健康成年杂种犬随机分为传统心脏停搏液(TBC)组和改良心脏停搏液(MBC)组。麻醉后建立体外循环(CPB)，CPB开始后5min阻断升主动脉，于主动脉根部灌注传统心脏停搏液或改良心脏停搏液。阻断2小时后开放升主动脉，应用多巴胺和/或肾上腺素支持循环功能，达停机指标后停机，再观察30min。在CPB前(T1)、升主动脉开放后5min(T2)、停机(T3)和停机后30min(T4)抽取中心静脉血测定血浆心肌肌钙蛋白I(cTnI)浓度和肌酸激酶同工酶(CK-MB)活性。记录各时点血流动力学指标、多巴胺用量以及辅助时间。实验结束前取左心室心肌全层行病理检查。结果：12只犬均顺利脱机，但TBC组辅助时间比MBC组长(P<0.05)，停机时多巴胺用量高(P<0.05)。血浆cTnI浓度和CK-MB活性在T1时点相似(P>0.05)，开放升主动脉后cTnI深度增高，但TBC组高于MBC组(P<0.05)，TBC组CK-MB活性也高于MBC组，但差异无统计学意义(P>0.05)。病理检查显示MBC组病理分级低于TBC组(P<0.05)。结论：与传统心脏停搏液相比，心脏停搏液中加入L-精氨酸、腺苷和组氨酸能减少变力性药物的用量，缩短辅助循环时间，减少cTnI、CK-MB的释放。

    关键词 心脏停搏液；心肌缺血/再灌注损伤；L-精氨酸；腺苷；组氨酸

    The Myoprotective Effect of the Blood Cardioplegic Solution with L-arginine,

    Adenosine and Histidine on the Myocardium during CPB in Canine.

    JIA Mengxing, DU Lei, YANG Pingliang, WANG Wei*, DIAN Ke*, LIU Jin

    (Department of Anaesthesiology, Department of Cardiothoracic Surgery*,Huaxi Hospital, Sichuan University, Chengdu 610041, China)

    Abstract Objective:To investigate if blood cardioplegic solution enriched with L-arginine, adenosine and histidine can improve the myocardial protection after ischemic reperfusion injury (I/R). Methods: 12 adult healthy mongrel dogs of either sex weighting from 17.5kg to 25kg were divided into two groups(TBC group and MBC group)at random, and then anesthetized and heparinized. Cardiopulmonary bypass (CPB) was set up. Aorta was cross-clamped and the heart was perfused antegradly from root of aorta with either traditional blood cardioplegic solution (TBC group, n=6) or modified blood cardioplegic solution (MBC group, n=6) enriched with 2 mmol/L L-arginine, 1 mmol/L adenosine and 10 mmol/L histidine at 29℃. After two hours ischemia, aorta was unclamped. Dopamine and/or adrenaline were used in order to wean from CPB. Cardiac troponin I (cTnI) and creatine kinase MB (CK-MB) were measured in two groups before CPB, 5 minutes after unclamping, at the end of CPB, and 30 minutes after CPB respectively. Hemodynamic data were also taken down. At the end of the experiment, specimens from left ventricles were taken for pathological examination. Results:All dogs were weaned from CPB successfully. The dosage of inotropic drugs of TBC group were higher than that of MBC group(P>0.05), and two dogs used adrenaline support in TBC group. Serum concentration of cTnI and activity of CK-MB of TBC group were also higher than that of MBC group. Pathological results showed that pathological grading was lower in MBC group than that in TBC group. Conclusion: Blood cardioplegic solution enriched with L-arginine, adenosine and histidine can reduce myocardial injury and leakage of cTnI and CK-MB 2 hours after ischemia during cardiopulmonary bypass in canine. ......