矽尘致肺泡巨噬细胞氧化损伤的超微结构和细胞化学研究

ULTRASTRUCTURAL AND CYTOCHEMICAL STUDY ON FREE RADICAL INJURY OF RAT ALVEOLAR MACROPHAGES BY SILICON DUST IN VITRO

目的：探讨矽尘致肺泡巨噬细胞损伤过程中是否存在着氧化损伤机制。方法：对矽尘作用于肺泡巨噬细胞产生的 Ｏ２和 Ｈ２Ｏ２进行原位显示、定量测定并做相关分析；以 ＡＴＰａｓｅ作为膜功能酶改变的反映；在亚细胞水平观察细胞形态结构。结果：细胞形态结构受损程度、膜ＡＴＰａｓｅ的活性与矽生致肺泡巨噬细胞早期产生的氧自由基活性直接相关。结论：（ｌ）首次将原位显示氧自由基技术应用于矽尘致肺泡巨噬细胞损伤机制研究，发现氧自由基的产生及其介导的进一步的自由基连锁反应是砂尘损伤肺泡巨噬细胞的机制之一，提示应用抗氧化剂减弱矽生所致的损伤，以预防肺成纤维细胞增殖，给临床用药提供了理论参考；（２）形态学方法定位显示氧自由基比自由基总体测定技术更能直观具体地阐明细胞损伤状况。为矽肺发病机制的研究提供了又一项实验技术。

To analyze the relationship between oxygen free radicals and the morphological damage of alveolar macrophages(AMs) induced by silicon dust. Mehtods: Cytochemical technqiue was used to demonstrate the oxygen radicals in situ. Meanwhile, the ultrastructure of AMs was observed. The cytochemical reaction of O2 and Mg2+-ATPase were analyzed quantitatively by image analyzer, and the linear correlation tendency between the quantitative results of the O2 and ATPase reactivity was elucidated. Rdults: Like opsonized zymosan A, toxic mineral particles, silicon dusts also could result in production of O2 and H2O2 on AMs. They were localized on the plasma membrane, the membrane of phagosome and/or pinosome and the lysosomal membrane. There was a close relationship between AMs morphological and enzymatic damage and the production of oxygen free radicals. Conclusion: (l) This paper firstly use the technique, which demonstrates the oxygen free radicals in situ to study the oxygen mechanism of the silicosis. Oxygen free radicals reaction induced by quartz and the free radical chain reaction is in one of the AMs damage mechanisms. Antioxidant may be given to patients to terminate oxygenic damage, and further protect evolvement of fibroblasts from proliferation. (2) Cytochemical technique to demonstrate O2 and H2O2 oxygen free radicals in situ is superior to other techniques in a sense. It is more convenient to observe the real situation of the oxidative damage on cells, making it easy to clarify the relationship between the production of free radicals and the damage degree on cells. It is a useful technique for studying the mechanisms of silicosis.