Abstract: OBJECTIVE To observe effects of sophocarpine to SOD， MDA and Connexin43 in acute myocardial ischemia rats induced by coronary artery ligation，to explore the mechanism of action of the sophocarpine and to provide laboratory evidence for the application of sophocarpine.METHODS The experimental animals which were divided into sham operation， model group， amiodarone group and different doses sophocarpine groups were administrated for 7 days，and were ligated the left coronary artery to induce SD rats myocardial ischemia， II lead electrocardiogram was recorded before， during and after model establishment. Blood from femoral artery was collected and its serum was separated to detect the content of SOD and MDA. The ischemic part of the rat's heart was selected for histological examination. Immunohistochemistry was applied to observe the distribution of CX34.RESULTS ① Compared with the sham group， SOD decreased significantly (P<0.01)， while MDA was significantly higher (P<0.01). Compared with the model group， amiodarone， sophocarpine middle dose group， sophocarpine big dose group SOD was significantly higher (P<0.05)， amiodarone， sophocarpine high-dose group MDA decreased significantly (P<0.05 ). CX43 expression within the cytoplasm. ②Compared with the sham group， model group， ST-T immediately after modeling and 24 hours was significantly higher (P<0.01). Compared with the model group， amiodarone group sophocarpine middle dose group， the high dose group of sophocarpine， after modeling instantly ECG ST-T was significantly depressed (P<0.01)， ST-T sophocarpine low-dose group depression (P<0.05). ③ Myocardial fibers within the cytoplasm of sham-operated and treated Cx43 expression compared with the model group， arranged chaos， amiodarone group， small-dose group of sophocarpine ， middle-dose group of sophocarpine ， high-dose group of sophocarpine， the average optical density value decreased significantly (P<0.01).CONCLUSION The sophocarpine can increase the content of serum superoxide dismutase， reduced malondialdehyde content， against myocardial ischemia-induced abnormal distribution of Connexin43.