脂多糖致衰老大鼠急性肺损伤及心肌组织ATP酶等的变化

Acute Lung Injury and Changes of Myocardial ATP Enzymes Induced by Lipopolysaccharide in Aging Rats

目的观察给衰老大鼠静脉或左心室内注入脂多糖(lipopolysaccharide,LPS)后,是否发生急性肺损伤(acutelunginjury,ALI)以及心肌组织ATP酶等的改变情况。方法雄性Wistar大鼠40只复制成衰老模型。然后随机分成对照组(静脉注射生理盐水,n=8),ALI组(静脉注射5mg/kg体重LPS,n=16),及LPS组(左心室内注入相同剂量LPS,n=16)。注射后2h或6h收集血并取肺、心。制备肺、心组织匀浆。测肺湿/干重量比,用比色法测定蛋白、乳酸(LA)、一氧化氮(NO)和丙二醛(MDA)含量以及谷胱甘肽过氧化物酶(GSH-PX)、Na+-K+-ATPase和Ca2+-Mg2+-ATPase活性。结果ALI组大鼠在静脉注射LPS后2h,肺泡灌洗液中蛋白含量及肺湿/干重量比显著升高(P<0.01);血中LA、NO2-/NO3-和MDA含量也显著升高(P<0.01);同时,肺组织中NO2-/NO3-含量显著升高(P<0.01),而GSH-PX及Na+-K+-ATPase活性均显著下降(P<0.01)。上述变化持续至注射后6h时。但在心肌组织中,直至注射LPS后6h才出现MDA含量的显著升高(P<0.01),和GSH-PX、Na+-K+-ATPase及Ca2+-Mg2+-ATPase活性的显著下降(P<0.01)。而在LPS组,注射LPS后2h的血和2h、6h时的肺组织NO2-/NO3-含量均显著升高(P<0.05);注射后2h时肺组织中Na+-K+-ATPase活性显著下降(P<0.05)。其它指标无显著改变。结论给衰老大鼠静脉注?

Objective To investigate whether acute lung injury(ALI)and changes of myocardial ATP enzymes were induced by intravenous or intraventricle of left heart injection of lipopolysaccharide(LPS)in aging rats.Methods 40male Wistar rats were used for reproducing aging animal model.Aging rats were randomly divided into aging control group (n=8),ALI group(LPS,5mg /kg body weight intravenous injection,n=16),and LPS group(same dosage LPS,intraventricle of left heart injection,n=16).The samples(blood,lung and heart)were collected at2,6hours after LPS or saline administration.Results Compared with aging control,protein content in bronchial alveolar lavage fluid(BALF),ratio of lung wet/dry weight and the LA,NO 2- /NO 3- and MDA contents in blood were increased markedly(P<0.01)at2,6hours in ALI group.The GSH-P X ,Na + -K + -ATPase activities in lung tissue were decreased significantly(P<0.01),but NO 2- /NO 3- content in lung tissue was increased obviously(P<0.01)at2hours in ALI group.These changes were maintained until at 6 hours after LPS administration.The above parameters were no obviously changes in myocardium at2hours after LPS administration in ALI group.But at6hours,MDA content was increased obviously(P<0.01);Na + -K + -ATPase,Ca 2+ -Mg 2+ -ATPase and GSH-P X activities in myocardium were decreased markedly(P<0.01).While in LPS group,only NO 2- /NO 3- contents were increased(P<0.05)in blood and lung tissue as well as Na + -K + -ATPase activity in lung tissue were decreased(P<0.05),another parameters had no obvious changes.Conclusions ALI was obviously formed by intravenous injection LPS after2,6hours in aging rats.Myocardial enzyme etc decreased only at6hours in ALI group.But above parameters were no obviously changes in LPS group.It was suggested that there was probable myocardial damage in rats of ALI group,and it was mainly induced by ALI.