一氧化氮合酶在去卵巢大鼠心肌缺血再灌注损伤中的调控作用

Regulative role of nitric oxide synthase in myocardial ischemia-reperfusion injury of ovariectomized rats

目的研究一氧化氮合酶(NOS)在去卵巢大鼠心肌缺血再灌注(IR)损伤中的调控作用。方法选取雌性SD大鼠132只,为探究去卵巢对心肌IR损伤的影响,48只大鼠随机分为假手术组、IR组、去卵巢组、联合组,每组12只;为探究内皮型NOS(eNOS)和诱导型NOS(iNOS)在去卵巢加重心肌IR损伤中的作用,84只大鼠IR造模前进行去卵巢、尾静脉注射过表达eNOS或敲低iNOS的腺相关病毒,分为阴性假手术组、阴性IR组、阴性联合组、eNOS+IR组、eNOS联合组、iNOS小干扰RNA(si-iNOS)+IR组、si-iNOS联合组,每组12只。检测每组心肌梗死面积、血清乳酸脱氢酶(LDH)、肌酸激酶同工酶(CK-MB)、LVEF、左心室短轴缩短率(LVFS)及心肌eNOS和iNOS的表达。结果与IR组比较,联合组心肌iNOS表达、心肌梗死面积、血清LDH和CK-MB水平增高,心肌eNOS表达、LVEF和LVFS水平降低(P<0.05)。与阴性联合组比较,eNOS联合组和si-iNOS联合组心肌梗死面积、血清LDH和CK-MB水平降低[(23.51±3.22)%、(26.21±2.93)%vs(58.78±5.42)%,(176.31±15.48)U/L、(169.52±17.12)U/Lvs(328.85±37.12)U/L,(35.41±6.41)U/L、(34.77±5.94)U/Lvs(88.73±9.14)U/L,P<0.05],LVEF、LVFS水平增高[(41.31±3.12)%、(42.09±3.41)%vs(30.77±2.15)%,(21.47±1.57)%、(21.32±1.42)%vs(15.92±1.33)%,P<0.05]。结论eNOS表达降低、iNOS表达增高可加重去卵巢大鼠心肌IR损伤。

Objective To investigate the role of nitric oxide synthase(NOS)in the regulation of myocardial ischemia-reperfusion (IR)injury in ovariectomized(OVX)rats.Methods A total of 132 female SD rats were subjected,and 48 of them were randomly divided into sham operation group,IR group,OVX group and combined group,with 12 in each group.In order to explore the role of endothelous NOS(eNOS)and inducible NOS(iNOS)in ovariectomization increasing myocardial IR inj ury,another 84 mice were divided into negative sham group,negative 1R group,negative combined group,eNOS+IR group,eNOS combined group,iNOS small interfering RNA(si-iNOS)+IR group and si-iNOS combined group,with 12 in each group.The mice of the corresponding groups were injected with adeno-associated virus(AAV)overexpressing eNOS or knocking down iNOS via tail vein before OVX modeling.Myocardial infarct size,serum levels of lactate dehydrogenase(LDH)and creatine phosphokinase isoenzyme(CK-MB),LVEF,LVFS,and expression levels of eNOS and iNOS in the myocardial tissues were measured.Results The combined group had significantly increased level of iNOS in myocardium,larger myocardial infarct size and elevated serum LDH and CK-MB levels,but decreased myocardial expression of eNOS and LVEF and LVFS values than the 1R group(P<0.05).When compared with the negative combined group,the myocardial infarct size and serum LDH and CK-MB levels were decreased[(23.51±3.22)% and(26.21±2.93)% vs(58.78±5.42)%,176.31±15.48 and 169.52±17.12 vs 328.85±37.12 U/L,35.41±6.41 and 34.77±5.94 vs 88.73±9.14 U/L,P<0.05],and the LVEF and LVFS values were increased[(41.31±3.12)% and(42.09±3.41)%vs(30.77±2.15)%,(21.47±1.57)% and(21.32±1.42)%vs(15.92±1.33)%,P<0.05]in the eNOS combined group and si-iNOS combined group.Conclusion The decrease of eNOS expression and increase of iNOS expression are related to the aggravation of myocardial 1R injury in OVX rats.