TNF在犬严重烧伤早期脑水肿中的变化及意义

Changes of TNF in the early stage of cerebral edema following severe burn and their significance in dogs

目的 探讨严重烧伤早期血浆TNF的变化与脑水肿形成的关系。方法 犬 5 2只分为对照组 (n =6)和单烧组 (n =6)、乳酸钠液组 (n =2 0 )及葡萄糖液组 (n =2 0 )。将致伤组犬制成 5 0 %TBSAⅢ度创面 ,于伤前及伤后 6、12、18、2 4h动态测定各组犬血浆TNF值并与脑病理组织学及含水量变化对比分析。结果 严重烧伤早期脑水肿模型 (葡萄糖液组 )伤后TNF水平和脑含水量呈持续升高 ,伤后 2 4h达峰值。电镜下伤后 6h后毛细血管内皮细胞及血管周围胶质细胞终足肿胀 ,神经细胞出现空泡状现象 ,毛细血管内皮细胞 ,神经细胞及轴突呈不同程度的缺血性改变。随着观察时间的延长 ,这种改变逐渐明显 ,以伤后 2 4h表现最为显著。

Objective To explore the relationship between the dynamic changes of tumor necrosis factor(TNF) and the development of cerebral edema at the early stage of severe burn. Methods Fifty two mongrel dogs were inflicted with 50% TBSA Ⅲ degree burns and divided randomly into control, simple burn(SB), sodium lactate solution group(SL) and glucose solution(GS) groups. The level of TNF was detected and compared with manifestation of histopathology and brain water content(BWC) at 6 h, 12 h, 18 h and 24 h before and after burn in each group respectively. Results The level of TNF and BWC in GS group elevated continuously and peaked at 24 h following burn. Histological changes of cerebral edema were observed at 6h following burn, accompanied by swelling of endothelial cells and peri vascular glial cells, presence of vacuolation in neurons at 12 h following burn, ischemic state of different degrees of capillary endothelium, neurons and axons. These changes became more marked with elapse of time and most obvious at 24 h following burn. Conclusion TNF may play a role in the development of cerebral edema at the early stage of severe burn.