Pre-treatment with radix astragali for myocardial cell apoptosis and its relative genes in rats with ischemic reperfusion

Shumin ZHAO; Li HAN; Lihui MA; Jian ZHOU; Xiangyu KONG

ABSTRACT

BACKGROUND:

Radix astragali has the effect of protecting cells from damage in ischemic reperfusion, whether pre-treatment with radix astragali can protect myocardial eells from apoptosis in ischemic reperfusion ?

OBJECTIVE:

To investigate the effect of pre-treatment with radix astragali on apoptosis and its relative genes in rats with ischemic myocardial reperfusion

DESIGN:

A randomized and controlled trial taking Wistar rats as experimental subjects.

SETTING:

The Basic Medical Department of Chengde Medical College and the Geriatric Department of the Affiliated Hospital.MATERIALS The experiment was completed in the Imunnohistochemical Laboratory of Basic Medical Institute in Chengde Medical College from February to December in 2004. A total of 30 healthy male Wistar rats were selected, and at random classified as groups of radix astragali pre-treated (radix astragali), ischemic reperfusion and psuedo-operated (control), 10 rats for each group.

METHODS:

Radix astragali injection was given peritonealy for rats in radix astragali pre-treated group before operation, and the equivalent normai saline was given for those in ischemic reperfusion and psuedo-operated groups. One week later, the model of ischemic reperfusion was set up. After operation the myocardia in marginal zone of ischemic reperfusion were sampled, and the myocardia of the corresponding zone were taken for control group. The method of terminal (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) was used for assay of myocardial apoptosis rate, and the ABC immunohistochemical method was used for assay of myocardial bcl-2 (inhibiting apoptosis gene) and bax (promoting apoptosis gene).MAIN OUTCOME

MEASURES:

Apoptosis rates, and expression of bcl2 and bax genes of myocardia

RESULTS:

① Apoptosis rate of myocardial cells The rate in radix astragali group was decreased compared with that in ischemic reperfusion group [ (14.06 ±9.97) ％, (19.34±12.30) ％, t = 1.863, P ＜ 0.05].② Expression of bcl-2 There was no significant difference between radix astragali and ischemic reperfusion groups[(9.14±4.46) ％, (8.99±4.54) ％, P ＜ 0.05].③ Expression of bax The expression in radix astragali group was decreased compared with that in ischemic reperfusion group [(12.65 ±7.23)％,(18.12±7.92) ％, t = 2.096, P ＜ 0.05]

CONCLUSION:

Pre-treatment with radix astragali can down-regulate the expression of promoting apoptosis gene so as to reduce the rate of myocardial cell apoptosis, hence it can protect the myocardial cells in ischemic reperfusion.