OBJECTIVETo observe the effect of Folium Panax quinquefolium saponins (PQS) on apoptosis of cardiac muscle cells (CMCs) and apoptosis-related gene expression in rats with acute myocardial infarction (AMI).

METHODSFifty Wistar rats were randomly divided into 5 groups, 40 rats underwent coronary ligation of left anterior descending branch to establish AMI rats model, while to the other 10 rats in the sham-operation group, thoracotomy without coronary ligation was carried out. The AMI model rats in treated groups were treated with high-dosage PQS, low-dosage PQS, captopril respectively for 7 days, and those in the control group were treated with normal saline instead. Then, the apoptotic CMCs were labeled by TUNEL and the expression of Bcl-2 and Fas in cardiac muscle cells were determined by immunohistochemical methods.

RESULTSThe apoptotic index of CMCs in the model rats (46.48%) was significantly higher than that in the sham-operation group ( 1.03%, P<0.01 ). CMCs apoptosis rate in the low-dosage PQS group, the large-dosage group and the captopril group was 23.53 %, 17.58 % and 25.17 %, respectively, all were significantly lower than that in the sham-operation group (P<0.01). The expression of Bcl-2 gene was up-regulated and expression of Fas protein was down-regulated in the three treated groups.

CONCLUSIONPQS can inhibit CMCs apoptosis in AMI rats, downregulate Fas protein expression and up-regulate Bcl-2 protein expression, and has antagonistic effect in myocardial ischemic injury.