Objective: To explore the protective effects of Panax quinquefolius saponins (PQS) and to investigate its possible mechanism on myocardial ischemia-reperfusion model of rats. Method: Fifty rats were randomly divided into 5 groups:sham operation group

model group

low-and high-dose PQS groups (100

300 mg·kg-1)

and nimodipine group (21.6 mg·kg-1) of 10 rats each. The myocardial ischemia-reperfusion model was induced by ligature of coronary artery and reperfusion of rats except for rats in sham operation goup. All rats were ig administrated with corresponding medicines once daily for 15 days. The heart function and cardiac infarction area were observed. The contents of creatine phosphokinase (CPK)

lactic dehydrogenase (LDH)

tumor necrosis factor (TNF) -α and interleukin (IL) -6 in serum and superoxide dismutase (SOD)

glutathion peroxidase (GSH-Px) and malonaldehyde (MDA) in cardiac muscle tissue were tested. Result: Compared with sham operation group

the left ventricular systolic pressure was increased

the left ventricular end-diastolic pressure was decreased

cardiac infarction area was increased

and the contents of CPK

LDH

MDA

TNF-α and IL-6 were decreased

the activities of SOD and GSH-Px were inhibited in model group (P<0.01

P<0.05). The above indexes were improved in the PQS groups (P<0.01

P<0.05). Conclusion: PQS can attenuate the damage caused by myocardial ischemia reperfusion and its mechanism may be involved with the anti-oxidation and anti-inflammatory activities.