Objective: To investigate the role of Shenfu injection(参附注射液) in rats with systemic(inflammatory) response syndrome(SIRS) and its mechanism.Methods: The SIRS model of rats were(replicated) by intravenous infusion of lipopolysaccharide(LPS).Fortyfive male Wistar rats were randomly divided into three groups,the control(C) group,the LPS injury group(L group) and the Shenfu injection treatment group((T group)).The model rats in(L group) and T group were divided into four subgroups(according) to different time points after LPS infusion(1,2,4,and 6 hours).The activation of nuclear(factorκB)(NFκB) in blood mononuclear cells and the contents of tumor necrosis factorα((TNFα)) and interleukin6(IL6) in plasma were detected by enzymelinked(immunoadsorbent) assay((ELISA)),the pathological changes of lung and liver were observed,and compared to those of the control group.(Results): After LPS injection,the activation of NFκB in mononuclear cells(increased) and reached the highest level at(2 hours)(0.604±0.020) in(L group),which was higher than that of C group(0.112±0.017).The level of TNFα increased and peaked at 2 hours((1 644.8±25.9) ng/L) in (L group),which was higher than that of C group((55.9±19.2) ng/L).The content of IL6 increased gradually with prolongation of time in(L group),which was higher than that of C group.Pathological examination showed that LPS could cause(pulmonary) alveolar hemorrhage,edema and inflammatory cell(infiltration) in lung tissue and congestion,(edema),capillary dilation and inflammatory cell(infiltration) in liver(tissue) in(L group).Shenfu injection could(reduce) the activation of NFκB and the level of TNFα,IL6,ameliorate the damage of lung and liver (tissue).Conclusion: Shenfu injection may play a(protective) role by inhibiting the activation of NFκB in(SIRS rats.)