Abstract: 【Objective】 To investigate the effect of trimetazidine (TMZ) on oxidative stress level

expressions of TNF -α and SOD -2 from myocardial tissue and cardiac function in the rats with type -1 diabetes induced by streptozotocin. 【Methods】 Thirty male Sprague -Dawley (SD) rats were randomly subdivided into three groups: Group N consisted of normal rats (normal control group

n = 10). Group C consisted of diabetic rats (diabetic controls

n = 10). Diabetes was induced by a single intraperitoneal injection of STZ at 40 mg/kg body weight in 0.1 M citrate buffered saline.Group TMZ consisted of diabetic rats (n =10) received TMZ (15 mg·kg-1·d-1) orally by gavage for 16 weeks. At 16 weeks

the final body weight(BW)

heart weight(HW)

and left ventricle weight(LVW) were recorded. And cardiac function and hemodynamic index were assessed by color doppler ultrasound and miniature pressure transducer (Millar Micro -Tip) respectivly. We also measured MDA level and the expressions of TNF -α and SOD -2 in the myocardial tissue and observed the myocardial morphology by HE staining. 【Results】 Compared with group N

LVW/HW

LVW/BW and MDA rose and the cardiac function decreased in group C (P < 0.05). There were lower protein expression of SOD -2 (P < 0.001)and higher protein expressions of TNF -α in group C than group N (P < 0.05). TMZ treatment successfully up -regulated the SOD -2 expression (P < 0.05)

down -regulated the expression of TNF -α(P < 0.05)

and reduced MDA level

LVEDP and LVW/HW (P < 0.05). 【Conclusion】 The increase of TNF -α protein expression and oxidative stress level may play important roles in the occurrence and development of diabetic cardiomyopathy.Trimetazidine may reduce the protein expression of TNF -α

decrease oxidative stress level and improve cardiac diastolic function.