测定胎盘型碱性磷酸酶判定烟雾吸入所致肺泡I型细胞损害

Determination of placental alkaline phosphatase (PLAP) for detecting the damages of alveolar type I cells caused by smoke inhalation

通过动态观察血浆及支气管肺泡灌洗液(BALF)中PLAP的变化,探讨烟雾吸入所致肺泡Ⅰ型细胞损害及其与肺损伤发生发展的关系,采用大鼠烟雾吸入伤模型,分别检测了正常对照及致伤2,6,12和24小时动物的动脉血气、肺水量、BALF中总蛋白和白蛋白含量,BALF和血浆中PLAP含量,并作了病理检查。结果表明:动物伤后出现急性呼吸衰竭和严重肺水肿,BALF中总蛋白及白蛋白含量明显升高;血浆及BALF中PLAP水平亦显著增加,且与BALF中蛋白含量的改变相关显著;病理检查亦见严重肺泡Ⅰ型细胞损害。提示PLAP不仅可作为肺泡Ⅰ型细胞损害的标志,而且与烟雾吸入伤后肺泡一毛细血管膜通透性增加有密切关系。

The placental alkaline phosphatase (PLAP) is a marker enzyme of alveolar type I cells. To evaluate the damages of alveolar type I cells and its relations with the development of acute lung injury caused by smoke inhalation, the present study was designed to observe the dynamic changes in PLAP contents in plasma and bronchoalveolar lavage fluid (BALF). Following the induction of smoke inhalation injury in rat, the arterial blood gas levels, lung water volume, total protein and albu- min contents in BALF, and PLAP contents in plasma and BALF were determined respectively in normal control and injured animals at 2,6,12 and 24h after injury. The pathomorphology of lung tissues was al- so observed. It was found that after smoke inhalation, animals showed acute respiratory failure and se- rious pulmonary edema. The total protein and albumin levels in BALF increased markedly. Both PLAP contents in plasma and BALF also increased dramatically, and there was a significant positive correla- tion between the changes in the PLAP and the total protein contents in BALF. The pathomor- phologically serious structural damage of alveolar type I cells were also found. PLAP may be not only a marker of alveolar type I cells injury,but also interrelated with the permeability increase of alveolar- capillary membrane after smoke inhalation.