OBJECTIVETo study the effect of Panax quinquefolius Saponin (PQS), an extraction from stem and leaf of American ginseng, on vascular regeneration in infarcted area, and expressions of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in myocardium of rats with acute myocardial infarction (AMI).

METHODSFifty male Wistar rats were established into AMI model successfully and randomly divided into 5 groups equally, i.e. the model group, the high, middle and low dose PQS groups and the metoprolol group. They were treated with saline, different doses of PQS (54 mg/kg x d, 27 mg/kg x d, 13.5 mg/kg x d)and metoprolol (4.5 mg/kg x d) respectively, by gavage once a day for 14 days. Besides, a sham operated group and a normal control group were set up for control with 10 rats in each group. All rats were killed on the 15th day. Six samples of heart were chosen from each group for examining expressions of VEGF, bFGF and the VIII coagulation factor under light microscopy by immunohistochemical staining, and the quantitative analysis on positive responsive intensity of VEGF and bFGF was conducted on the other 4 heart samples using the image analysing system, then mean micro-vessel density (MMVD) was calculated.

RESULTSThe expressions of VEGF and MMVD were higher in the high and the middle dose PQS groups than those in the model group (P < 0.05) and the expression of bFGF was higher in the three PQS groups than that in the model group (P < 0.05).

CONCLUSIONPQS can protect myocardium from ischemic injury in rats after AMI by way of promoting angiogenesis in the infarcted or ischemic area of myocardium and up-regulating expressions of VEGF and bFGF in myocardial cells.