西洋参茎叶三醇组皂苷对急性心肌梗死大鼠的保护作用

目的：研究西洋参茎叶三醇组皂苷（PQTS）对大鼠急性心肌梗死的保护作用，阐明其作用机制。方法：采用结扎左冠状动脉前降支制备大鼠急性心肌梗死模型，将大鼠随机分为假手术组、梗死模型组、阳性药苦碟子注射组及PQTS 12.5、25.0、50.0 mg•kg-1组，各组动物每日腹腔注射给药1次，连续3 d。计算急性心肌梗死24 h后的心肌梗死面积（MIS），测定血清肌酸磷酸激酶（CK）、乳酸脱氢酶（LDH）、天门冬氨酸氨基转换酶（AST）、超氧物歧化酶（SOD）活力及丙二醛（MAD）、一氧化氮（NO）、游离脂肪酸（FFA）含量，观察全血低切（10/s）、中切（80/s）、高切（160/s）黏度及血浆黏度，并测定血小板聚集功能。结果：与梗死模型组比较，PQTS各剂量组急性心肌梗死大鼠的MIS明显缩小(P<0.05)，血清CK、LDH、AST活性及FFA、MAD含量降低(P<0.05或P<0.01)，血清SOD活性及NO含量提高(P<0.05)，全血低、中、高切黏度及血浆黏度、血小板聚集率明显降低(P<0.05或P<0.01)。其作用与阳性药苦碟子注射液相当。结论：PQTS对大鼠急性心肌梗死具有明显保护作用，可能与其增强抗氧化酶活性，减少氧自由基对心肌的损伤，纠正心肌缺血时FFA代谢紊乱，降低血液黏度以及血小板聚集功能等有关。

Protective effect of panax quinquefolium 20s-protopanaxtriolsaponins on acute myocardial infarction in rats

Objective To study the protective effect of panax quinquefolium 20s-protopanaxtriolsaponins(PQTS) on acute myocardial infarction in rats,and to clarify its mechanism.Methods The acute myocardial infarct model was prepared by left anterior descending coronary occulusion for 24 h in openchest anesthetized rats.The rats were divided randomly into sham group,ischemia-reperfusion model group and PQTS 12.5,25.0,and 50.0 mg·kg-1 groups.All animals were administered one time everyday with intraperitoneal injection(i.p) for 3 d.The myocardial infarct size(MIS) was calculated.The activities of serum creatine hosphokinase(CK),lactate dehydrogenase(LDH),aspartate aminotransferase(AST) and superoxide dismutase(SOD),and the contents of malondialdehyde(MDA),nitric oxide(NO) and free fatty acid(FFA) were determined.Blood was collected to observe low shearing specific viscosity,middle shearing specific viscosity and high shearing specific viscosity of whole blood and plasma viscosity.At the same time,the platelet aggregation rate was also determined.Results Compared with model group,the MIS in the rats treated by PQTS(in dosages of 12.5,25.0 and 50 mg·kg-1·d-1,i.p×3 d) were significantly reduced(P<0.05);the activities of serum CK,LDH and AST,and the contents of serum FFA and MDA were declined(P<0.05 or P<0.01);the activitie of SOD,and the content of NO were increased markedly(P<0.05).In addition,the low shearing specific viscosity,middle shearing specific viscosity and high shearing specific viscosity of whole blood and plasma viscosity as well as platelet aggregation rates were also declined significantly(P<0.05 or P<0.01).Conclusion PQTS has a significant protective effect on acute myocardial infarction,which may be related to increasing the activity of antioxidase in body,scavenging the damage of peroxidation from oxygen free radicals,correcting metabolic disorder of FFA in myocardial ischemia,and decreasing the viscosity of blood and plasma and function of the platelet aggregation etc.