烧伤早期中性粒细胞粘附的改变及其机制的探讨

目的：探讨烧伤早期血液中性粒细胞（PMN）粘附的变化规律及其机制。方法：采用兔30％ TBSA Ⅲ度烧伤,于伤后即刻,2,4,8,16,24,48 h取血分离获得PMN,测定PMN粘附率及其粘附分子CD11a/CD18的变化;同时检测血浆中PLA2和TNF的改变。结果：烧伤早期PMN粘附率及粘附分子CD11a/CD18均明显高于伤前组,尤以伤后8 h为最显著,然后逐渐下降,至48 h后恢复至烧伤前水平，PMN粘附率与CD11a/CD18两者之间呈明显的正相关(r=0.90)；烧伤后血浆中TNF，PLA2也开始升高,分别于烧伤后即刻与24 h达峰值。结论：烧伤早期PMN粘附率及粘附分子CD11a/CD18均明显升高；粘附分子CD11a/CD18可能是介导烧伤后PMN粘附的重要因素；烧伤早期TNF,PLA2的变化可能也是PMN粘附改变的原因之一。

Changes and mechanism of polymorphonuclears adhesion during early stage of burn injury

Objective: To investigate changes of polymorphonuclears(PMNs) adhesion and the possible mechanism after burn injury. Methods: Fourteen rabbits were subjected to a burn of nearly 30%TBSA with full-thickness burned area about 30%. PMNs were obtained from blood through Percoll gradient centrifugation. The PMN adhesion molecule CD11a/CD18 was measured by CAMs ELISA. Levels of TNF and PLA2 in plasma were measured by radioimmunoassay. Results: The PMN adhesion molecule CD11a/CD18 in rabbits increased markedly after burn, peaked at 8 h, restored to the level of control after 48 h. The PMN adhesion rate of rabbits also increased markedly after burn , peaked at 8 h, restored to the level of control after 48 h. It was found that there was significant linear relationship between the PMN adhesion molecule CD11a/CD18 and PMN adhesion rate (r = 0.90). The level of TNF in plasma was higher in burned groups than that in 0 group, peaked at once. The level of PLA2 in plasma was higher after burn than in 0 group, peaked at 2 h. Conclusion: The PMN adhesion molecule CD11a/CD18 and adhesion rate are increased after burn injury. The results suggest that CD11a/CD18 plays an important role in PMN adhesion after burn injury. The levels of TNF and PLA2 in plasma rise rapidly after burn injury, and the rise occurs before or at the same time as the changes in PMN adhesion molecule and PMN adhesion rate. They might contribute to the changes in PMN adhesion molecule and PMN adhesion rate after burn injury.