论文部分内容阅读
目的:在猪心肌缺血再灌注模型上,观察等容血液稀释和缺血预处理对再灌注损伤心肌的保护作用。方法:18头小型猪建立急性心肌缺血模型,随机分为3组:对照组(组Ⅰ,n=6),缺血预处理组(组Ⅱ,n=6),缺血预处理加血液稀释组(组Ⅲ,n=6),测定心排血量(CO),混合静脉血氧饱和度(SvO2,)、冠状动脉血流量,计算心肌氧供,氧耗量。于钳扎前、解除钳扎后20,60min分别测定血浆中丙二醛(MDA),SOD活性、磷酸激酶(CPK)及肌酸磷酸激酶同功酶(CK-MB),自左心耳剪下标本,测定HSP70mRNA表达率。结果:①缺缺血20min时3组MAP、CI及SVRI明显减低(P<0.01),但I组下降幅度明显大于II,III组。再灌注60min时,II组,III组HR明显低于对照值(P<0.01),III组HR的变化则无统计学意义,I组MAP,CI的下降幅度明显大I组和II组(P<0.05).②再灌注20min及60min时,III组的冠脉血流量明显大于I组(P<0.05)。③再灌注20min和60min时,3组CPK,CPK-MB均较对照值明显升高(P<0.05-0.01),组I的升高幅度明显大于组II,组III。组ⅠSOD值在再灌注20min,60min时逐步降低(P<0.05),组II,组IIISOD值有升高趋势,与对照值比较,无统计学意义。再灌注60min时,组ⅠMDA值明显高于组Ⅱ,组Ⅲ。④组ⅠHSP70mRNA表达低于组Ⅱ和组Ⅲ。结论:等容血液稀释可明显增强预适应拮抗心肌缺血再灌注
Objective: To observe the protective effect of isovolemic hemodilution and ischemic preconditioning on myocardial reperfusion injury in pig model of myocardial ischemia-reperfusion. Methods: A total of 18 piglets were randomly divided into 3 groups: control group (group Ⅰ, n = 6), ischemic preconditioning group (group Ⅱ, n = 6), ischemic preconditioning plus blood Dilution group (group Ⅲ, n = 6), cardiac output (CO), mixed venous oxygen saturation (SvO2) and coronary blood flow were measured to calculate myocardial oxygen supply and oxygen consumption. Plasma concentrations of malondialdehyde (MDA), superoxide dismutase (SOD), phosphokinase (CK) and creatine phosphokinase isoenzyme (CK-MB) Specimens were tested for HSP70 mRNA expression. Results: (1) MAP, CI and SVRI were significantly decreased in the three groups at 20min after ischemia (P <0.01), but the decrease in group I was significantly greater than that in II and III groups. The HR of group II and group III was significantly lower than that of control group (P <0.01) at 60 min after reperfusion. The change of HR in group III was not statistically significant. The decrease of MAP and CI in group I was significantly greater than that of group I and II <0.05) .② At 20 minutes and 60 minutes after reperfusion, the coronary flow in group III was significantly greater than that in group I (P <0.05). ③ At 20 min and 60 min after reperfusion, the CPK and CPK-MB in 3 groups were significantly higher than those in control group (P <0.05-0.01). The increase of group I was obviously greater than that of group II and group III. The SOD value of group Ⅰ decreased gradually at 20 min and 60 min after reperfusion (P <0.05). The values of IIISOD increased in group II and group II compared with the control group, but there was no statistical significance. At 60 min after reperfusion, the value of group Ⅰ MDA was significantly higher than that of group Ⅱ and group Ⅲ. ④ group Ⅰ HSP70mRNA expression lower than group Ⅱ and group Ⅲ. Conclusion: Isotonic hemodilution can significantly enhance preconditioning against myocardial ischemia-reperfusion