Effects Of Xinnaotong On Myocardial Ischemia And Reperfusion Injury In Rats

Background It is known that myocardial ischemia injuiy is mainly occurs in ischemia heart disease (HID) and results from the failing balance of the cardiomyocyte demanding for oxygen and the blood suppiy by the coronary arteries. Improving the coronary circulation ~4ll be benificial to prevent the process of the injury, Rebulding the local coronary circulation such as percutaneous transluminal coronary angjoplasty (PTCA), intracoronaiy thrombolysis is the basic treatment to IHD . As the reperfusion injury might be increased after reperfiision and the effect of the Ireatment was lowered , it is necessary to arrange some cytoprotection drugs to assist the rebuilding treatment Xinnaotong (XNT) Capsule, which consists of Soivia miltiorrhiza,Crataeguspinnalifida and Ginkgo biloba L could dissipate blood stasis , remove food retention and promote digestion Previous phamiacological studies showed that they might have the effect of cytoprotection. Objectives To study the effects of XNT on acute myocardial ischemia injury and reperfusion injury and elucidate its cytoprotection mechanisms in vivo and in Vitfl). Methods 1. Effect on AM7I 56 Wistar rats were divided randomly into seven groups (n=8) Control , Model , AIvll+XNT 250mg. Kg?, iWll+XNT 500mg. Alvll+XNT 1000mg . Kg1 , propranolol (AMI+PRO 6mg . g1) Diaoxinxuekang (AMI+DAO 60mg. Kg1) . The rats were administered lv I- ?F~ {~5~ respectively for ten days One hour after the last administration , the left anterior descending coronazy arteiy (LAD) of the rats was ligated with a 6/0 non-injuiy ligature needle 10 hours later , the changes electrocardiogram (EKG) myocardial infarction size (MIS), lactate dehydrogenase (LDH) and creatine kinase (CK) in serum of rats were measured. 2. Effect on MRI: 56 Wistar rats were divided randomly into seven groups (n=8): Control , Model (MRI) , (l黤angdanshen pill) , MRJ+XNT 250mg. Kg-i, MRI+XNT 500mg . Kg梚 , MRI+XNT l000mg . Kg-i , MRI+PRO 5mg. Kg-i, MRI+FDS 80mg . Kg-i . The drugs were given orally to rats for 14 days . One hour after the last administration, LAD of the rat was ligated with a 6/0 non- injuiy ligature needle. 30 minutes after the ligation , the ligature was released to make the model of reperfution. The changs of EKG, CK in serum, endothelin (ET) and nitric oxide (NO) in plasma, superoxide dismutase (SOD) and malondialdehyde (MDA) in myocardium and the supermicrostnicture were investigated 3 hours after the reperfusion. 3. Effect on cardiomyocytes with hypoxia (HyO) Neonatal rat cardiomyocytes were cultured in the medium with hypoxia for ten hours. The cells were divided into seven groups (n5) Control , Model (H/R) , HyO+XNT 30mg . , HyO+XNT 60mg. V?, HyO+XNT 120mg. V?, HyO+PRO 0.5mg HyO+FDS 5mg. V1 . The content of LDH was measured. 4. Effect on cardiomyocytes with hyopoxia / reoxygention (HIR) Neonatal rat cardiomyocytes were cultured in the medium with six hours hypocia followed two hours reoxygenation . The cells were divided into seven groups (n=5) Control , Model (l-IJR) , HJR+X1~JT 30mg . V?, H/R+XNT 60mg. HJR+XNT 120mg. li, I-IIR+PRO 0.5mg . 111, WR+FDS 5mg. V1. The content of LDH and MDA was measured ; Neonatal r...