大鼠烟雾吸入伤后肺表面活性物质磷脂组分含量的变化及意义

为探讨烟雾吸入后肺表面活性物质（ＰＳ）磷脂组分含量的变化和可能机理及其与ＰＳ活性抑制和肺功能损害的关系，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小时大鼠静态肺顺应性（Ｃｓｔ）、支气管肺泡灌洗液（ＰＡＬＦ）表面张力活性、ＢＡＬＦ和肺匀浆总磷脂（ＴＰＬ）、磷脂酰胆碱（ＰＣ）、磷脂酰肌醇（ＰＩ）、磷脂酰丝氨酸（Ｐｈｓ）、磷脂酰乙醇（ＰＥ）含量、ＢＡＬＦ和肺匀浆中磷脂酶Ａ２（ＰＬＡ２）活性。结果表明动物伤后Ｃｓｔ显著降低；ＢＡＬＦ最小表面张力（ＳＴｍｉｎ）进行性升高；ＢＡＬＦ中ＴＰＬ增加，但ＰＣ（％ＴＰＬ）明显降低，且与Ｃｓｔ和ＳＴｍｉｎ的变化相关显著；肺组织内ＴＰＬ及ＰＣ均下降，并与其中ＰＬＡ２活性升高明显相关。结论：烟雾吸入伤早期肺内ＰＳ磷脂组分含量明显改变，ＰＣ相对含量减少是引起ＰＳ活性抑制及肺功能障碍的主要原因之一，ＰＬＡ２可能在ＰＳ组分异常和（或）含量减少中起重要作用。

Changes and significance of phospholipid composition contents of pulmonary surfactant after smoke inhalation injury in rats \

Objective:To evaluate the changes and possible mechanisms of phospholipid composition contents of pulmonary surfactant (PS),and to investigate the relationship between these changes and the PS activity inhibition,as well as pulmonary dysfunction after smoke inhalation.Methods:Following the induction of smoke inhalation injury in rats,static lung compliance (Cst),surface tension properties of bronchoalveolar lavage fluid (BALF),the contents of total phospholipids,phosphatidylcholine(PC),phosphatidylinositol (PI),phosphatidylserine (Phs),phosphatidylethanolamine (PE),and the activities of phospholipase A 2 in BALF and lung tissues were determined respectively in normal control and injured animals at 2,6,12 and 24 h after injury.Results:After smoke inhalation,the static lung compliance decreased markedly.The minimum surface tension (STmin) of BALF increased progressively.The TPL level in BALF increased,while the PC relative content (% TPL) reduced dramatically with pronounced correlation between its change and the changes of Cst,as well as STmin.Both TPL and PC contents in lung tissues decreased,while their changes correlated significants with the increase of phospholipase A 2 activity.Conclusion:The change in phospholipid composition contents of PS in lungs occur at the early stage after smoke inhalation.The decrease of PC relative content is one of the main causes to induce PS activity inhibition and pulmonary dysfunction.PLA 2 may play an important role in introducing abnormality of PS composition and/or decrease of PS content.