Objective:To approach the variation and relation of serum IL-6、IL-4 with IaAg on lung alveolus macrophage cell face in MODS rats

to illuminate the roles of proinflammatory/antiinflammatory balance and immune stage in MODS pathogenesis. Methods:MODS rat modes were established by intraperitoneally injected with low-lose zymosan after rats were subjected to 12 hours of instestine ischemia-reperfusion. Serum levels of IL-6、IL-4 and expressinon of IaAg were determined by Enzyme-Linked immunosorbant assay(ELISA). Results:Compared with rats of sham-operated group

those of model group showed manifest pathological change in all important organs after 6 hours. Followed by time after injury

serum levels of IL-6、IL-4 in model group were increased gradually. Expression of IaAg on lung alveolus macrophage cell face decreased gradually. Conclusion:During MODS serum levels of proinflammatory cytokine(IL-6) and antiinflammatory cytokine(IL-4) increased significantly. In earlier period

proinflammatory response predominated. In later stage antiinflammatory response prevailed. Disequilibrium of the two resulted in the development of MODS. Immunosupression developed later. At this time antiinflammatory response gained advantage. The ratio of IL-6 to IL-4 was related closedly to the degree of Immunosupression.