An Expermental Study Of Mechanism Of Acute Respiratory Distress Syndrome Induced By Oleic Acid In Rats And Effect Of Salvianolate

Abjective:To investigate the content of atrial natriuretic peptide(ANP), B-type natriureti c peptide(BNP), malondialdehyde(MDA), superoxide dismutase(SOD) and the change of Na+-k+-adenosine triphosphatase(NKA) level on the acute respiratory distress. syndrome rats, and to explore the mechanism of Salvianolate on the treatment of ARDS.Methods:①30rats were randomly divided into three groups, the oleic acid group and S-alvianolate Group. control group:insert the vein catheter into the femoral vein after abdo minal anesthesia by the urethane, and then the rats will be given the injection of4.0ml/kg of saline solution.oleic acid group:insert the vein catheter into the femoral vein after abdo minal anesthesia by the urethane, and then the rats will be given the injection of oleic acid (0.1ml/kg) and saline solution(1ml/kg).Salvianolate group:insert the vein catheter into the femoral vein after abdominal anesthesia by the urethane, and then the rats will be given t he injection of Salvianolate (30mg/kg) and saline solution(lml/kg).②Insert the arterial c-atheter into the femoral artery after the above operation, then take the appropriate blood sample into the test tube and put them into the refrigerator on the degree of-40. The rats would be killed by arterial exsanguination. The content of ANP,BNP,MDA and SOD wer e determined by ELISA assay.③Remove and weigh the left pulmonary segment separat ely before and after drying blood, put the rest into the refrigerator on the degree of-70an d detect the content of MDA, SOD and NKA use the biochemical technique.Results:①Biochemical index and W/D:in the oleic acid group and Salvianolate group, the left lung W/D and content of ANP, BNP,MDA were significantly elevated compared with the control group, and the content of SOD and NKA were obviously decreased(p<0.01). It also showed significant difference between oleic acid group and S-alvianolate gro up(p<0.01).②The ANP and BNP level in blood and MDA,SOD,NKA level in left lung tissue were associated with the W/D of the left lung(p<0.01), the conten-t of MDA and S-OD were associated with the NKA level of the lung tissue. The index of the lung tissue was associated with the blood index.③Pathological changes observed by light microscop e through HE stain:in the oleic acid group, we can observe the nuclear en-richment, kar-yolysis and karorrhexis, lobular interstitium thickness. It’s easy to see the e-xudative alv-eolar edema fluid, neutrophil and red blood cell in the alveolar cavity and th-e alveolar a-trophy. In the location with gentle pathological changes, we can see the hyaline membra nes, we can see lobular interstitium thickness and edema, neutrophil infiltration and edem -a around the capillary. In the Salvianolate group, the degree of pathological changs were more gentle than the oleic acid group, we can see the less tissue necrosis, less alveolar atr-ophy, the edema fluid and neutrophil infiltration decreased. Foamy cells can be observed. In the control group, we can see no pathological changes.④We can see the edema and ne-crosis of type Ⅰ epithelial cells, and the changes were more severe in the type Ⅱ epithelia-1cells. We can the degeneration and different vacuoles in size. In the Salvianolate group, the changes were more gentle than the oleic acid group and there is no changes in the control group.Conclusion:①The ANP and BNP level in blood serum, the content of MDA, SOD, N KA in lung tissue are both associated with W/D, promoting the degree of the lung dama ge.②Our research proved negative correlation property between MDA level in lung ti-ssue,the content of NKA activity in lung tissue,which indicates MDA may decrease th-e production of NKA or promote deactiviation of NKA③Our research proved Negati-ve correlation property between the ANP,BNP level in blood serum and the content of NKA in lung tissue. Tips may reflect the progress of the process of lipid peroxidetion.④Our research proved negative correlation property between the ANP,BNP level in bl ood serum and the content of NKA in the lung. Tips may reflect the degree of pulmona-ry edema.⑤Salvianolate can inhibit the increase of ANP and MDA, it can also inhibit-t the decrease of BNP, SOD, NKA, reduce the edema and necrosis,which suggests tha t the Salvianolate can act on the pathogenesis of ARDS through different ways. Salvian olate can treat the rats with ARDS caused by oleic acid.