Studies Of Protective Effects And Mechanisms Of Guihong Capsule On Myocardial Ischemia Injury

Objective: To study the protective effects of Guihong capsule against acute myocardial ischemia hypoxia in rats.By recording the survival time of mice under closed normobaric hypoxia and establishing the model of acute myocardial ischemia in rats,to observe the survival time of each group of mice under closed normobaric hypoxia,the changes of T waves and J points of Electrocardiogram(ECG), the levels of creatine kinase(CK),creatine kinase-MB(CK-MB),loctate dehydrogenase(LDH),superoxide dismutase(SOD) and malonaldehyde(MDA) in the serum were determined respectively,the percentage of myocardial infarction, myocardial apoptosis index(AI) and the Bcl-2, Bax protein expression.Preliminary discussion on its mechanism of action, in order to provide theoretical basis for Guihong capsule in the treatment of coronary heart disease(CHD).Methods: 1?Subcutaneous injection of isoprenaline(ISO) to mice can increase the speed of myocardial oxygen consumption.By recording the survival time of mice to observe the situation of hypoxia.2 ? With myocardial ischemia induced by pituitrin(Pit) injection,recording the standard ? lead ECG in 0~5min,observing the changes of T waves and J points.Then took blood via abdominal aorta after 1h of acute myocardial ischemia,determined the levels of CK,CK-MB,LDH,SOD and MDA.3?Built the model of acute myocardial infarction through the ligation of anterior descending coronary artery,6h latter killed the rats,cut the heart into 5~6 pieces,immersed in 0.25% NBT phosphate buffer solution.Then cut the ischemic myocardial for weighing, calculate the percentage of myocardial infarction.4?Built the model of acute myocardial infarction through the ligation of anterior descending coronary artery,4h latter killed the rats,cut out the left ventricle,and immersed in 10% neutral formalin buffer.Using HE staining to observe the morphological changes,detection of AI by SABC and the the expression of Bcl-2, Bax protein by SABC.Results: 1?Each group of bearing hypoxia at normal pressure in mice were significantly increased(P<0.05 or P<0.01).2?Each group of rats were changed in T waves and J points after injection of Pit.The results showed that each grop of Guihong capsule can against myocardial ischemia injury in different degree caused by Pit(P<0.05 or P<0.01).The influence of serum enzyme levels caused by acute myocardial ischemia in rats after injection of Pit:Compared with the model rats,the high group of Guihong capsule(HGHC) and the middle group of Guihong capsule(MGHC) could reduce the CK,CK-MB activities and MDA contents in serum,increase SOD activities at the same time(P<0.05 or P<0.01).The HGHC also could reduce the LDH activities(P<0.05).The low group of Guihong capsule(LGHC) could have no obvious difference compared with the model rats.3?Compared with the model rats:myocardial infarction area were reduced and had statistically difference in radix salviae miltiorrhizae cardiotonic pill(RSMCP),MGHC and HGHC(P<0.05 or P<0.01).There were no statistically difference in LGHC.4?The results of HE staining:The sham group's myocardial morphology were basic normal.The model group of myocardial cells were disordered arrangement,no boundaries, some areas of myocardial fibers were ruptured, necrosis.Each group of Guihong capsule could significantly reduce the situation of myocardial pathology,the myocardial fibers in neat rows compared with the model group,and no obvious swelling volume.The results of AI:Compared with the model rats,there were statistically difference in RSMCP,MGHC and HGHC(P<0.01).But no statistically difference in LGHC.The results of Bcl-2, Bax protein expression:Compared with the model rats,the expression of Bcl-2 protein had significantly increased in RSMCP,MGHC and HGHC(P<0.01).But no statistically difference in LGHC.Bax protein had decreased with statistically difference in each group(P<0.05 or P<0.01).As the increase of the dose,Bcl-2/Bax ratio were increased.Conclusion:Guihong capsule can increase the time of bearing hypoxia at normal pressure,improve the myocardial oxygen consumption and metabolism.It also can expand blood vessels,reduce myocardial tissue peroxide,reduce the percentage of myocardial infarction and AI,enhance the expression of Bcl-2 protein and reduce the expression of Bax protein and improve the Bcl-2/Bax ratio.Guihong capsule can protect the myocardial ischemia,the mechanism for these could have related to expanding the blood vessels, improving blood flow and reducing myocardial oxygen consumption.