| ObjectiveMyocardial ischemia reperfusion injury is common in clinical practice organ damage,its exact mechanism is not very clear.The previous study show that myocardial ischemia reperfusion injury is an acute inflammation.The increasing of IL-1βin myocardial ischemia reperfusion is one of the important reasons that lead the cardiac dysfunction and myocardial necrosis.If we can inhibit the the formation of IL-1βwe can reduce the damage of cardiac cells,whicth it is also beneficial to the recovery of myocardial function.In recent years,traditional Chinese medicine has been made some progress in controlling of the myocardial ischemia reperfusion injury.Xue Bi Jing Injection is abstracted from 36 prescriptions of traditional Chinese medicine, having the properties of anti-bacterial toxin,decreasing the level of endotoxin regulating immunity and inflammatory mediators,improving microcirculation, protecting the vascular endothelial cells etc.In this study,we will observe the protective effects of Xue Bi Jing Injection on myocardium during ischemia-reperfusion and explore its possible mechanism by using of the Langendorff isolated heart model,whitch can ruled out the effects of the nerve fluid and peripheral vascular resistance,and other factors to the drug,thereby providing rational clinical application.MethodsThirty health adult Wistar rats with no restrictions on male and female weighting from 180-220 grams were randomly divided into two groups:test groups -Xue Bi Jing Injection groups and control groups respectively(n=15 per group).After anesthesia induction with 10%Chloral Hydrate by intraperitoneal injection and heparinization(heparin-sodium intraperitoneal injection 1000 U/kg for each Wistar rat) hearts were excised rapidly,rinsed thoroughly in chilled 4℃Krebs-Henseleit buffer(K-H buffer),connecting the aortic cannulation to the the isolated Langendorff perfusion model,and then perfused retrogradely in the isolated Langendorft model,at a constant perfusion pressure of 75cmH2O,with 37℃oxygenated K-H buffer.After 15 minutes equilibration,the hearts were perfused retrogradely with cardioplegia(Test group:implicated Xue Bi Jing Injection in St ThomasⅡsolution(4ml/100ml);control group:St ThomasⅡsolution only).All these hearts received 30 minutes of global ischemia and reperfused with K-H solution at 37℃until 120 minutes.The samples of myocardium of left ventricle were collected after the experiment is completed,and then be fixed in 4%paraformaldehyde at 4℃for 20h.The tissue was then dehydrated, embedded in paraffin,and sectioned(5 p,m sections)in a standard manner.The other sample of myocardium was excised and then frozen rapidly and stored at -70℃.We collected and measured the coronary outflow of fluid flow at pre-ischemia and 60,120 minutes of reperfusion respectively(ml/min),and detected CK of the collected effluent with automatic biochemistries' detecting instrument and viewing the morphology changes of myocardium by optical microscope.Then detecting IL-1βwith ELISA. Statistical analysis:all measurement data is expressed as X±s and statistical significance was evaluated by multiple comparison of T test and ANOVA.A P value of 0.05 or less was considered to indicate statistical significance.All statistical processes were completed via SPSS(V13.0).ResultsChanges of cornory flow:Compared with control group,the CF was significant raised in test group(Xue Bi Jing Injection) at 60,120 minutes after reperfusion(P＜0.05); Changes of CK in the collected coronary effluent:Compared with control group,the decreases of CK were significant in test group(Xue Bi Jing Injection) at 60,120 minutes after reperfusion(P＜0.05);Myocardial morphology changes:The endocardium in control group was found oedema,hemangiectasis and hyperaemia in some parts of myocardium and inflammatory cell infiltration in myocardium.However,the cadiocyte are normal on the whole and the oedema is not very obvious comparatively; Concentration of MDA in myocardium:Compared with control group,the concentration of MDA was significantly decreased in test group(Xue Bi Jing Injection) after reperfusion(P＜0.05);Concentration of IL-1βin myocardium:Compared with the control group,the concentration of IL-1βwas significantly decreased in test group (Xue Bi Jing Injection) after reperfusion(P＜0.05).ConclusionXue Bi Jing Injection could increase CF,inhibit the release of CK,relieve the injury of cadiocyte,protect Myocardial membrane while MIRI;Xue Bi Jing Injection could obviously improve myocardial ultrastructure after MIRI,therefore,it has the ability of myocardial preservation;Xue Bi Jing Injection could significantly decreased IL-1βand MDA in myocardium.And it may provid myocardial preservation after MIRI by this way. |
