Abstract: Objective To explore the protective effect and mechanism of fistular onion bulb（FOB） extraction on myocardial cell apoptosis in ischemia-reperfusion（I/R） model rats. Methods Thirty-six male SD rats were randomly divided into the sham group（n = 12），the I/R group（n = 12）and the FOB group（n = 12）. The anterior descending branch of the left coronary artery was ligated and reperfused for 45 minutes. Multi-channel physiological recorder recorded the changes of left ventricular function，TUNEL staining was used to observe the myocardial cell apoptosis and calculate the myocardial cell apoptosis rate；Western blot was used to detect the expression of p-p38，p53 protein in myocardial AAR，BZ，and RA；RT-PCR detected myocardial tissue p38，p53 mRNA expression. Results Compared with the sham group，the heart function of the I/R group was significantly impaired，the apoptosis rate increased，the expression levels of p-p38 ，and p53 protein were significantly increased，and the relative expression level of p53 mRNA was significantly increased（P < 0. 05）；FOB pretreatment improved the rat heart function，the apoptosis rate decreased，the expression levels of p-p38，and p53 protein decreased，and the relative expression level of p53 mRNA was downregulated （P < 0. 05）. Conclusion The FOB can improve the cardiac function of I/R rats，which is related to the regulation of p38 MAPK signal pathway protein expression and anti-cardiomyocyte apoptosis.

Key words: fistular onion bulb extraction, ischemia-reperfusion, apoptosis, p38 MAPK