ABSTRACT
Objective: To study the protective effect of the total flavones in Microcos paniculata (TFMP) on the acute myocardial ischemia (AMI) induced by isoprenaline (ISO) and its mechanism. Methods: The rats were ig administered with TFMP (8, 4, and 2 mg/kg) once daily for consecutive 5 d, and the AMI rat model was established by sc injection with ISO (2 mg/kg) 1 h after the last administration. The effects of TFMP on the electrocardiogram (ECG) at different time points and the myocardial tissue pathological histomorphology dying by hematoxylin were observed; The superoxide dismutase (SOD) and malondialdehyde (MDA) levels of myocardial tissue, glutathione peroxidase (GSH-Px), lactate dehydrogenase (LDH), and creatine kinase (CK) activities in serum were detected using biochemical method. Results: Compared with the model group, the high- and mid-doses (8 and 4 mg/kg) TFMP inhibited the J spot downward of ECG during myocardial ischemia (P < 0.05), especially after 10 min of ISO injection. The myocardial injury induced by ISO was aslo improved in these two groups, the levels of LDH and CK in serum (P < 0.05) and the content of MDA in myocardial homogenate (P < 0.01) were decreased, the activities of SOD (P < 0.01) and GSH-Px (P < 0.05, 0.001) in the myocardial homogenate were increased. Conclusion: The TFMP has the apparent protective effect on AMI injury, its mechanism may be related with improving the myocardial anti-oxidative ability and decreasing the oxidative stress reaction.