Objective To investigate the effects of procyanidin on rat myocardial inflammatory reaction and TNFα (tumour necrosis factor α) expression.

Methods The rat myocardial infarction model was established by left anterior descending coronary artery ligation. Survived rats were randomly divided into the myocardial infarction control group (MI n=9) and the procyanidin group (PC n=9, treated by 100 mg/(kg/day)), and another sham group (sham n=10), Each group was further divided into by 2W and 4W: MI2W and 4W, PC2W and 4W, sham2W and 4W (5/group). Conditions of inflammatory cellular infiltration in the infarcted and non-infarcted zone were observed at two and four weeks after MI with histopathological methods, The expression of TNFα was detected by semiquantitative RT-PCR, the expression of inflammatory protein of TNFα was detected by immunohistochemistry and Western blotting.

Results After MI two and four weeks, procyanidin group compared with the MI control, the gene and protein expression of TNFα was lower (p<0.01), the inflammatory cellular infiltration was milder, compared with sham group, on the level of gene and protein, MI and PC groups have statistical difference (p<0.01).

Conclusion Procyanidin can attenuate the myocardial inflammatory reaction and suppress the expression of TNFα.