最适浓度L-精氨酸在心肌缺血再灌注损伤中作用的研究

Discussion on Optimal Content of L-arginine in Cardiac Ischemia-Reperfusion

目的 观察不同浓度的L-精氨酸(L-arginine,L-arg)在大鼠心肌缺血再灌注损伤中的作用及最适浓度的研 究。方法 在心肌缺血前给予含不同浓度L-arg的KH灌注液,再灌注期间测定心脏功能指标及冠状动脉流出液心 肌酶释放量如乳酸脱氢酶(Lactate dehydrogenase,LDH)和肌酸磷酸肌酶(Creatine phosphokinase,CPK),冠状动脉流 出液一氧化氮(Nitric Oxide,NO)含量,测定心肌组织丙二醛(Malondialdehyde,MDA)含量,观察心肌超微结构改变。 结果 心肌缺血前给予含低浓度L-arg的KH液(10,30,50 mmol／L)灌注心脏,能减轻心肌缺血再灌注损伤,其中 30 mmol／L组又优于其它两组,而心肌缺血前给予含高浓度L-arg的KH液(100mmol／L)灌注心脏明显加重心肌缺 血再灌注损伤。结论 L-arg在心肌缺血再灌注操作中有双重作用,既有有益一面,又有有害一面,不同浓度L-arg 的KH液灌注有不同的作用,可能存在一个最适浓度。

Objective To discuss the optimal content of L-arginine on myocardial ischemia reperfusion injury in rat. Methods Langendorff models were used with provision of different contents of L-arginine before myocardial ischemia. During reperfusion, cardiac function index and lactic dehydrogenase（LDH） activity, NO level, myocardial MDA etc. were observed. Results Low content L-arginine（ 10,30,50 mmol/L） could decrease myocardial ischemia reperfusion injury, among which 30 mmol/L L-arg was the best, while high content L-arginine（ 100 mmol/L） could increase myocardial ischemia reperfusion injury. Conclusion It seems that optimal content of L-arg exists. High content L-arginine has toxic effects while low content L-arginine has beneficial effects.