Objective: To investigate the effect of Bistortae Rhizoma n-butyl alcohol extract (PBNA-413) on cardiocyte apoptosis in rats with myocardial ischemia-reperfusion(MI/R) injury. Method: Thirty male Sprague-Dawley rats were randomly divided into five groups:sham group

MI/R model groups

low-dose

middle-dose and high-dose (0.1

0.3

1.0 mg ·kg-1) PBNA-413 treatment groups (n=6). The models of MI/R injury were established by ligating the left anterior descending coronary artery for 40 min and then reperfusing for 60 min

and the electrocardiogram (ECG) was recorded. Western blot analysis and Real-time PCR were utilized to measure B-cell lymphoma-2 (Bcl-2)

Bcl-2 associated X protein (Bax)

cysteine aspartate protease-3 (Caspase-3) and Caspase-9 mRNA and protein expressions in the ischemic and reperfusion region. Result: After myocardial ischemia

ECG ST-segment and T-wave in MI/R vehicle group were significantly higher than those in sham group(P<0.05

P<0.01)

but they were significantly decreased in the PBNA-413 treatment groups (P<0.01)

particularly in middle and high-dose groups. Compared with Sham group

protein and mRNA expressions of Bcl-2 (P<0.01) were decreased

while Bax

Caspase-3 and Caspase-9 were increased in MI/R vehicle group(P<0.05

P<0.01). Compared with MI/R vehicle group

the middle-dose PBNA-413 group showed an increased protein expression of Bcl-2 (P<0.05

P<0.01)

but decreased expressions of Bax

Caspase-3 and Caspase-9 (P<0.05

P<0.01). Except for Caspase-9

mRNA expressions of Bax

Bcl-2

and Caspase-3 showed similar changes with protein expressions. Conclusion: PBNA-413 may play a protective role against MI/R injury in rats by inhibiting cell apoptosis.