OBJECTIVETo investigate effects of Shenfu injection on the concentrations of plasma tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), activity of Nuclear Factor kappa B (NF-kappaB) and heart tissue ultrastructure during myocardial ischemia/reperfusion (I/R) injury in rats and its potential mechanism.

METHODSMyocardial ischemia/reperfusion (I/R) was produced by ligation and release of the left anterior descending coronary artery. Ischemia lasted for 30 min and reperfusion for 60 min. Twenty-four healthy male SD rats weighing 230-280 g were randomly divided into three groups (n = 8, each): Group I (Sham-operation group); Group II (I/R group); Group III (Shenfu group), in which Shenfu injection (10 ml/kg) was intraperitoneally injected 30 min before ischemia in animals with I/R. The plasma concentrations of IL-6 and TNF-alpha were measured by ELISA, and the heart was harvested for determination of NF-kappaB levels by Ecl-western blot analysis. Electron microscopy was used to study its ultrastructure.

RESULTSAfter reperfusion, NF-kappaB binding activity in myocardial nuclei and the plasma concentrations of IL-6 and TNF-alpha were significantly increased in Group II, compared with Group I (P < 0.01), and they were markedly reduced in Group III, compared with Group II (P < 0.01). In addition, electron microscopic examination showed more serious injury of the myocardium ultrastructure in Group II, while in Group III the myocardial ultrastructure was similar to normal state.

CONCLUSIONSShenfu injection inhibits NF-kappaB activity in I/R myocardium and leads to down-regulation of proinflammatory cytokine expression, which might be one of the molecular mechanisms of Shenfu injection in cardioprotection.