Study On The Protective Mechanism Of Shixiaosan In Ischemia-reperfusion Injure Of Myocardia Of Rabbits

Myocardial ischemia /reperfusion injury refers to the phenomenon of myocardial cellular metabolic or functional disorder and structural damage resulted from reperfusion to the ischemic areas. How to greatly reduce the degree of MIRI had already become an important research subject in the treatment of acute myocardial infarction. Multiple target effect, which represented the holistic characteristic of Chinese Materia Medica, made the Chinese herbs have great advantage in the prevention and treatment of the MIRI.ObjectsThis study was designed to explore the protective effect and its mechanism of JIAWEISHIXIAOSAN to MIRI model by measuring the changes of cardiac contractility, the incidence of arrhythmias, the level of SOD, MDA, and CK in serum, and the level of SOD and MDA in myocardial tissue after the JIAWEISHIXIAOSAN administration, which had some guiding significance for the study of Chinese Materia Medica on MIRI.MethodsForty rabbits were divided randomly into 5groups: sham operation group, model group, low dose group of jiawei shixiaosan, middle dose group of jiweishixiaosan and high dose group. The ischemia and ischemia-reperfusion models were made by ligating the left anterior descending branch of coronary artery. SOD, MDA and CK in serum of the experimental rabbits were detected separately before ischemia, after ischemia 30min and reperfusion 60min;The +dp/dtmax and -dp/dtmax in left ventricular pressure ,SOD and MDA 0f myocardial tissue were detected;The incidence of arrhythmias and the change of ST segment in electrocardiogram were detected when ischemia-reperfusion models were made.ResultsIn 30min after ischemia and 60min after reperfusion the activities of the serum SOD in the model group were decreased significantly compared with those in sham operation, and the serum MDA, CK in the model group were increased significantly compared with those in sham operation.The activities of the serum SOD in every experimental group given jiawei shixiaosan were higher significantly than those in model group, and the serum MDA, CK in the experimental group given jiawei shixiaosan were lower significantly than those in model group. The change of the content of the serum SOD, MDA, CK were associated significantly with the dose of jiawei shixiaosan. The +dp/dtmax and -dp/dtmax in left ventricular pressure in every group given shixiaosan were significantly higher than the model group (p<0.05) in dose-dependent manner. The vitality of SOD significantly decreased in I/R groups (p<0.05), and the vitality SOD of treatment groups was significantly higher than those in the model group (p<0.05). The myocardial tissue MDA in I/R animals was significantly higher than sham operation group (p<0.05), while the cardiac tissue MDA in every treatment group decreased significantly compared with model group (p <0.05). The incidence of arrhythmias in every treatment group were significantly longer (p<0.05). The duration of arrhythmias and the incidence of ventricular arrhythmias were significantly lower (p<0.05). In 15min and 60min after reperfusion, the degree of ST segment rising of model group was significantly higher than that of sham operation group (p<0.05). The degree of ST segment rising of every group given jiawei shixiaosan was significantly lower than that of model group (p<0.05). ConclusionJiawei shixiaosan has protective effect on ischemia-reperfusion injure of myocardia in rabbits through reducing the activity of SOD and removing oxyradical. Jiawei shixiaosan can enhance systolic and diastolic function of ischemia-reperfusion injury myocardial .Jiawei shixiaosan has preventive and protective effect on ischemia-reperfusion arrhythmias in rabbits...