严重烫伤大鼠早期肺组织TNFmRNA表达及其细胞定位

感染引起的各种介质过度释放，尤其是肿瘤坏死因子（ＴＮＦ）在肺损伤病理过程中发挥了重要作用。笔者应用斑点杂交、原位杂交等方法，检测了大鼠烧伤后ＴＮＦｍＲＮＡ在肺组织的表达及其细胞定位。结果证实，烧伤后肺组织ＴＮＦｍＲＮＡ表达迅速升高，伤后６小时达顶峰，２４小时仍维持较高水平，其动态变化与腔静脉血浆内毒素变化一致。原位杂交发现，在伤后３－６小时主要是肺间质巨噬细胞、肺泡巨噬细胞和肺泡Ⅱ型上皮细胞表达Ｔ

Early Expression and Cellular Localization of TNF mRNA In Lung Tissues of Rats After Severe Burn

Infection is one of the predisposing causes of lung failure.Overproduction of mediators induced by infection,especially TNF,plays an important role in the infection induced lung injury.The kinetic expression and cellular localization of TNF mRNA in the lung tissure was investigated using a rat burn model by the dot blot analysis and in situ hybridization.The results showed that after burn,the quantity of TNF mRNA increased rapidly and reached the maximal expression at 6th hour and there still remained a high level 24 hours after burn.The dynamic change of the quantity of TNF mRNA was similar to that of endotoxin plasma level in caval vein.By in situ hybridization,most of the cell expression of TNF mRNA at 3 6 hours postburn were macrophages located in interstitial tissue,alveolar macrophages and type II alveolar cells.PMN might be the predominant source of TNF mRNA at 12 24 hours postburn.It is considered that endotoxin may be the principal stimulative factor for early expression of TNF mRNA in the lung tissue postburn.TNF secreted by macrophages could not only elicit lung injury directly,but also mediate both PMN migration and activation to worsen the lung injury.(Original aritcle on page 107)