逐级再灌注对缺血心肌的保护作用

PROTECTIVE EFFECTS OF GRADUAL REPERFUSION ON ISCHEMIC MYOCARDIUM

本文旨在探讨逐级再灌注对心肌缺血──再灌注损伤的保护作用。离体豚鼠心工作模型，心脏缺血停搏１２０ｍｉｎ后再灌注６０ｍｉｎ。再灌注时，对照组以５．３９ｋＰａ常规压力行ｌａｎｇｅｎｄｏｒｆｆ灌流１５ｍｉｎ，再转为工作心状态。实验组则在Ｌａｎｇｅｎｄｏｒｆｆ灌注期间，逐级提高灌注压，分别以１．９６、２．９４和５．３９ｋＰａ的压力各灌注５ｍｉｎ。结果显示：控制性再灌注可减轻心肌超微结构损伤，降低心肌肌酸磷酸激酶释放及促进心脏功能的恢复。其作用机理可能与抑制再灌注早期心肌细胞膜上的Ｎａ＋－Ｈ＋交换活性有关。

The study dealt with the protective effects of gradual reperfusion on myocardial ishemia-reperfusion injuries. Isolated Guinea pig hearts were employed as the experimental models and were given 120 minutes of ischemic arrest followed by 60 minutes of reperfusion.During reperfusion,the hearts in the control group were given Langendorff perfusion at the pressure of 5.39kpa for 15 minutes,while those in the experimental group were reperfused at the gradual pressure,i.e.,at the pressures of 1.96、2.94 and 5.39kpa respectively for 5 minutes.Results suggested that control reperfusion could attenuate the damage of myocardial ultrastructure,decrease the release of CPK and improve cardiac functions. It was estimated that the mechanism might lie in the inhibition of Na+-H+ exchange in myocardial sarcolemmic membrane during the early period of reperfusion.