3，4-二-O-甲基-1，2，5，6-四硝酸甘露醇酯对冠状动脉结扎大鼠心肌缺血的保护作用

 目的 研究3，4-二-O-甲基-1，2，5，6-四硝酸甘露醇酯（3，4-di-O-methyl-1，2，5，6-D-mannitol tetranitrate，DMMTN）对冠状动脉结扎所致大鼠急性心肌缺血的保护作用及其作用机制。方法 以结扎左冠状动脉前降支方法建立大鼠急性心肌缺血模型，建立假手术组、心肌梗死模型组、鲁南欣康组、DMMTN低、中、高剂量（15，30，60 mg·kg^-1）组，测定手术后不同时段心电图ST段和T段的抬高；并于手术3 h后硝基四氮唑蓝( NBT) 染色法测定心肌梗死面积；测定血清中肌酸激酶（CK）、乳酸脱氢酶（LDH）、丙二醛（MDA）和超氧化物歧化酶（SOD）。结果 DMMTN能显著缩小心肌梗死面积，抑制术后心电图ST段和T段的抬高；能显著降低CK和LDH的活力，以及MDA的含量，同时能显著提高SOD的活力。结论 DMMTN对冠状动脉结扎所致大鼠急性心肌缺血具有显著的保护作用。

Protective Effects of 3,4-di-O-methyl-1,2,5,6-D-Mannitol Tetranitrate on Myocardial Ischemia Induced by Ligating Coronary Artery in Rats

OBJECTIVE To study the effects of 3,4-di-O-methyl-1,2,5,6-D-mannitol tetranitrate(DMMTN) on acute myocardial ischemia induced by ligating coronary artery in rats.METHODS Acute myocardial ischemia model was developed by ligating the anterior descending branch of left coronary artery in rats.The rats were randomly divided into 6 groups: sham group,model group,Lunanxinkang group,low-dose(15 mg·kg-1) DMMTN group,middle-dose(30 mg·kg-1) DMMTN group and high-dose(60 mg·kg-1) DMMTN group.The changes of ST segment and T segment of electrocardiogram at different moment were recorded after myocardial ischemia injury.At 3 h after ligation,the myocardial infarct size was measured by nitroblue tetrazolium(NBT) staining method.And the activities of creatine phosphokinase(CK),lactate dehydrogenase(LDH) and superoxide dismutase(SOD),and the content of malondialdehyde(MDA) were determined to evaluate the protective effects of DMMTN.RESULTS DMMTN could reduce the size of myocardial infarct significantly,inhibit the rising of ST segment and T segment of electrocardiogram,decrease the level of CK,LDH and MDA,and increase the activity of SOD.CONCLUSION DMMTN showed obvious protective effects on acute myocardial ischemia induced by ligating the coronary artery in rats.