Effects of losartan and ginseng on cardiomyocyte Bcl-2 gene expression induced by ischemia and reperfusion

Li WANG; Hesong ZENG; Zhengxiang LIU; Xiaochun LIU

ABSTRACT

BACKGROUND:

The studies found that cardiomyocyte apoptosis is related to ischemia-reperfusion injury directly. The clinical and experimental studies proved that ginseng and losartan could improve myocardial iscbemia and prevent the ischemia-reperfusion injury.But the comparative study of their effects on cardiomyocyte injury induced by ischemia and reperfusion has not been reported.

OBJECTIVE:

To compare the effects of ginseng and losartan on cardiomyocyte Bcl-2 gene expression after ischemia and reperfusion in vivo.

DESIGN:

Randomized controlled experiment.

SETTING:

Department of Cardiovascular Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology.MATERIALS The experiment was carried out in the Laboratory of Cardiovascular Internal Medicine of Tongji Hospital of Tongji Medical College Affiliated to Huazhong University of Science and Technology from November 2002 to April 2003. Totally 40 healthy adult Wistar rats, weighting 200-250 g, of either gender, were selected and divided into 4 groupssham operated group, ischemia-reperfusion group, ginseng treated group and losartan treated group with 10 rats in each group.

METHODS:

Rats were modeled in ischemia-reperfusion group, ginseng treated group and los arran treated group but not in sham operation group.20 mg/kg (1 mL in volume) losartan was given by stomach. The first administration was 2 hours prior to operation. Subsequently, the second and third administrations were given in immediate and 24 hours after operation,respectively; 1 mL of radix ginseng rubra (1 g/mL) was given by stomach.The first administration was 2 hours before operation. Subsequently, the second and third administrations were given in just and 24 hours after operation, respectively. The rats in ischemia-reperfusion and sham-operated group were given the normal saline with the same volume and at the same time. Immunohistochemistry and in situ hybridization histochemistry were used to measure mRNA and protein of Bcl-2 gene expression that were compared with those in the control group.MAIN OUTCOME

MEASURES:

The expression level of Bcl-2 mRNA and Bcl-2 protein in ginseng treated group and losartan treated group.

RESULTS:

Data of totally 40 rats was entered the final analysis. ① Content of Bcl-2 mRNA and protein were not significantly different both in ginseng group and control group (P ＞ 0.05). ② Contents of Bcl-2 mRNA and Bcl-2 protein were higher in ginseng treated group than those in the ischemia-reperfusion group (P ＜ 0.05 or 0.01).

CONCLUSION:

Expressions of Bcl-2 mRNA and Bcl-2 protein in ginseng treated group are higher than those in losartan treated group, which suggests that ginseng has not same effect with losartan in inhibiting cardiomyocyte apoptosis and in preventing and curing cardiomyocyte injury induced by ischemia-reperfusion.