CAJ | 학술논문

目的观察在体全心脏实施缺氧预处理的心肌保护效果.方法选用健康比格犬随机分为空白对照组(C组,n=8)与缺氧预处理组(HPC组,n=8),分别在全身麻醉下开胸建立双体外循环(体循环+冠脉循环)模型,HPC组通过冠脉体外循环对在体全心脏实施缺氧预处理(缺氧3 min,复氧5 min,重复3次),C组不实施缺氧预处理;两组均实施冷灌注使心脏停搏,体外循环60 min后观察犬复跳成功率、心律失常发生率以及除颤次数等临床表现;复跳后30 min结扎冠状动脉的左前降支主干中下1/3,60 min后观察心肌梗死的面积,并取标本做电镜分析;在T1(术前)、T2(体外循环开始前)、T3(复跳后即刻)、T4(缝扎冠状动脉的左前降支30 min后)分别检测肌钙蛋白水平和心肌酶谱;并观察两组间心脏舒缩功能和心肌超微结构的影响.结果 HPC组在T3时点心肌酶谱水平高于C组(P＜0.05),但在T4时点HPC组的心肌酶谱和肌钙蛋白均显著低于C组(P＜0.05);HPC组在一次性复跳率和除颤例数数上均有显著低于空白对照组(7/8比4/8、1/8比5/8,P＜0.05),HPC组心梗面积显著低于C组[(15.37±1.64)％比(29.77±3.38)％,P＜0.05],电镜显示HPC组线粒体结构的损害及心肌细胞水肿的程度轻于C组.结论在体全心脏缺氧预处理对于心肌细胞有显著的保护作用,能够提高心肌细胞对缺氧的耐受能力.
목적 관찰재체전심장실시결양예처리적심기보호효과.방법 선용건강비격견수궤분위공백대조조(C조,n=8)여결양예처리조(HPC조,n=8),분별재전신마취하개흉건립쌍체외순배(체순배+관맥순배)모형,HPC조통과관맥체외순배대재체전심장실시결양예처리(결양3 min,복양5 min,중복3차),C조불실시결양예처리;량조균실시랭관주사심장정박,체외순배60 min후관찰견복도성공솔、심률실상발생솔이급제전차수등림상표현;복도후30 min결찰관상동맥적좌전강지주간중하1/3,60 min후관찰심기경사적면적,병취표본주전경분석;재T1(술전)、T2(체외순배개시전)、T3(복도후즉각)、T4(봉찰관상동맥적좌전강지30 min후)분별검측기개단백수평화심기매보;병관찰량조간심장서축공능화심기초미결구적영향.결과 HPC조재T3시점심기매보수평고우C조(P＜0.05),단재T4시점HPC조적심기매보화기개단백균현저저우C조(P＜0.05);HPC조재일차성복도솔화제전례수수상균유현저저우공백대조조(7/8비4/8、1/8비5/8,P＜0.05),HPC조심경면적현저저우C조[(15.37±1.64)％비(29.77±3.38)％,P＜0.05],전경현시HPC조선립체결구적손해급심기세포수종적정도경우C조.결론 재체전심장결양예처리대우심기세포유현저적보호작용,능구제고심기세포대결양적내수능력.
Objective To investigate the myocardial protective effect of hypoxic preconditioning in thein vivo canine hearts.Methods Healthy beagle dogs were randomly divided into two groups:the hypoxic preconditioning group (HPC group,n =8) and the control group (C group,n =8).The dog model of the double cardiopulmonary bypass (systemic and coronary circulation) was established after chest opening under general anesthesia.In HPC group,dog hearts were perfused by the coronary circulation and subjected to hypoxic preconditioning (3 min of hypoxia followed by 5 min of reoxygenation,repeated 3 times).The animals in C group were not subjected to hypoxic preconditioning.Both groups underwent cold cardioplegia perfusion through coronary circulation to induce cardiac arrest.At 60 min after cardiopulmonary bypass,we observed one-time rebeat rate,the incidence of arrhythmia and electric defibrillation times.At 30 min after rebeating,the left anterior descending coronary arteries were ligated with suture at the lower 1/3.The myocardial infarction area size was observed 60 min later,and samples were taken for examination by electron microscopy.At T1 (before operation),T2 (before cardiopulmonary bypass),T3 (immediately after the rebeat),and T4 (30 min after the ligation of left anterior descending coronary),the troponin and myocardial enzymes spectrum were measured.Cardiac function and myocardial structure were also observed in both groups.Results Myocardial enzymes at T3 were higher in HPC group than in C group (P ＜ 0.05),and myocardial enzymes and troponin at T4 were significantly lower in HPC group (P ＜ 0.05).As compared with C group,one-time rebeat rate and defibrillation times were significantly reduced in HPC group (7/8 vs.4/8 and 1/8 vs.5/8,P＜0.05).The infarct area size was significantly smaller in HPC group than in C group [(15.37 ± 1.64) ％ vs.(29.77 ± 3.38) ％,P ＜ 0.05],and electron microscopy revealed that the damage of mitochondrial structure and edema of cardiomyocytes were significantly reduced in HPC group as compared with C group.Conclusion Hypoxia preconditioning of the whole heart in vivo had protective effect on myocardia.It could improve the tolerance of myocardia to hypoxic injury.