摘要Background Epidermal burn injury may trigger significant apoptosis of the spleen cells,which might be caused by a burninduced systemic inflammatory reaction.Heparin has been shown to possess anti-inflammatory properties.Interleukin 1 (IL-1) is centrally important among pro-inflammatory cytokines.We hypothesized that heparin might inhibit burn-induced apoptosis in the spleen via suppression of the IL-1 pathway.Methods Burn injury was performed on IL-1 R+/+ (IL-1 receptor wild-type mouse) and IL-1 R-/-(IL-1 receptor knockout mouse) mice,and they were then treated with heparin,saline or IL-1 receptor antagonist IL-Ra.Apoptosis,IL-1α and IL-1β expression were assessed in the spleens and serum.Survival curve analysis was further applied to elucidate the mechanism of heparin's protective properties.Results Burn induced significant apoptosis (sham:3.6％±2.1％ vs.burn:28.8％±5.9％; P ＜0.001)and remarkable expression o IL-1α and IL-1β in the mouse spleens and serum.Heparin reduced the burn-induced apoptosis in the spleens (heparin treated:8.6％±3.4％,P ＜0.005),which could be blocked by IL-1Ra.Heparin markedly decreased both IL-1α and IL-1β expression in the spleens and serum of burned mica.IL-1 R-/-mice demonstrated considerably less apoptosis in the spleens and had a higher survival rate after burns.Heparin did not significantly decrease apoptosis in the spleen and the mortality rate in IL-1 R-/-mice after burns.Conclusion Heparin inhibits burn-induced apoptosis of the spleen cells by suppressing IL-1 expression in mice.